The Łowicz dialect or the Księżak dialect is a dialect of Polish spoken by the ethnographic group of Łowiczans (Księżaks) inhabiting the historical region known as the Duchy of Łowicz around the cities of Łowicz and Skierniewice in south-western Masovia. It belongs to the Masovian dialect group and borders the Near Mazovian dialect to the north and east, the Lesser Polish Masovian Borderland dialect to the southeast, and the Łęczyca dialect to the south and west.

The classification of the Łowicz dialect is debated; in the past it has been considered a Lesser Polish dialect, but there are many features placing it within the Masovian group – the Łowicz dialect shows many transitional features between Masovia, Lesser Poland and Greater Poland. Currently, the dialect is often considered a trasitional dialect.

Features shared with Masovian dialects: ra- re-: redlić, redzić ja- > je-: jerzmo, jerzyny Leveling of pretent tense jedzie to jadzie 'a > 'e: spowiedać, wietrok, zamietać Simplification of consonant clusters after decomposing soft labial consonants by a reduction of the spirant: In the words ćwartka, śwat, śwatło, świerk, śwynia In the nominal instrumental plural ending: cepamy In instrumental plural endings of adjectives and pronouns: z nimy, z tymy dobrymu In enclitic pronominal forms: boli mi, dej my Leveling of nominative and genitive stems of neuter nouns: ciemię-ciemia siemię-siemia Contamination of the dative singular endings -owi + -u > -owju > -oju: chłopokoju Use of the third person plural past formsleli, sieli, śmieli sie based on mieli Replacement of neuter -ę nouns denoting young animals with -ątko: gynsiontko, koźlontko, kurconko or Replacement of neuter -ę nouns denoting young animals with -ak: cielok, koźlok, kurcok The comparative form cinzejsy (standard cięższy) Replacement of the infinitive ending -eć with -ić//-yć: lezyć, siedzić, wyjrzyć, zajrzyć, zlecić Use of the iterative suffix -ywać: zajmywać, znajdywać Lack of the morphemes -ow-, -yw- in kupać, zjmać, zlotać Features shared with Lesser Polish dialects A change of slanted á to o: bijok, bratowo, luśnio, do nos, zycio A merging of slanted é with e: bieda, brzeg, mleko Replacement of ablauted 'o with 'e: biedro, mietła, niese, piełun, pierun, wiesna A change of i, y > e before liquids: iN > eN: jendyk, jenny yN > eN: z tem, z temi dobremi iL > eL: lelijo, pieła, sielny iR > eR: drugie roz, fieranka yL > eL: beł, kobelła, motel yR > eRL derechtur Lowering of uN to oN: gront A tendency to harden labial consonants in conjugation (first person singular present): grzebe, kope Dissimilation of the clusters: tw > kw: kwardy tch > ćch: ćchórz tw > cw: cwaróg, łacwo Reduplication of s, ś > ss, śś in the terms bosso, wiesso sie, wiśsi and potential further dissimilation to sc, ść in bosco, powieścić, wiści (wisi) Dissimilation of the clusters: chw > kw: kwast, kwila, pokwoluny, zukwały chrz> krz: krzan, krzciny, krześniok, śpikrz rzch > rzk: wierzk kt > cht: chto, dochtur, ducht, dyrechtur, tracht k > ch: chłopotać sie, łocchnąć się Assimilation of kk > tk in letki, mintki (miękki) Use of the old dual ending -wa in the imperative: nieśwa, piswa, zawieźwa Replacement of -wa- with -ja- in dajać, wstajać Change of the prefix roz- > ôz-: ôzporek, na ôzgun, ôzwora Features shared with Greater Polish dialects Decomposition of ą Finally: jadom Medially before plosives: chomonto, gołomb Decomposition of ę Medially before a plosive: gołymbia, pynto, zymby Replacement of labial w with labial b in brzodziana, grzyba, knubie, trzeźby Change of rnk > rk: ziorko (ziarnko) Diminutive forms such as gornysek, kamysek, promysek, słunysko (słoneczko) Use of the adjectival endings -ity (barcyty, wodnity) and -aty (kolcaty, liściaty, pasiaty) The adverbial comparative forms -i||-y: nizy (niżej), późni, wyzy. Features shared with both Masovian and Lesser Polish dialects Masuration Use of -wa in The First person plural present: jedziewa First person plural past: nieśliśwa First person plural imperative: napiswa Use of the adjectival endings -isty (barcysty, piacysty, wodnisty) and -asty (gliniasty, graniasty, jiglasty) Features shared with both Lesser Polish and Greater Polish dialects A change of the imperative -aj > -ej: cytej Secondary e in the prepositions w, z: we wodzie, ze sokiem Labialization of initial o- > ô-: ôbora, ôko, ôwiec Secondary nasalization not motivated by a nasl consonant: gorsynt, myntryka, tompola, warząchew Voicing of c to dz in the comparative of adverbs: kródzy (krócej) Partial or complete reduction of medial ł ending a consonant cluster: kunica (kłonica), mynorz (młynarz) Interterm voicing: brad matki (brat matki), laz rośnie (las rośnie) Assimilation and simplification of strz, zdrz, trz, drz: oszcze (ostrze), nożdża (nozdrza), szczała (strzała) A change of rs to sz: gasztka (garstka), napasztek (naparstek) Retention of -i in numeral declension for the numerals 5-10: piuńci, szóści, siódmi The use of the suffix -ąckę in the deverbal adverb na stojąckę motivated by the government of the preposition na and resulting from the combination of the suffixes -ący with -ka, -kę, -ki Occurrence of the forms dońdę (dojdę), póńdę (pójdę)

Phonology Typical of Greater Polish as well as Lesser Polish dialects, voicing of word-final consonants before vowels and liquids is present here, including before clitics: jag jyno, mugeś (mogłeś). Some villages show devoicing under influence from Standard Polish. Typical of Masovian and Lesser Polish dialects is the presence of mazuration with very few exceptions,; this process is being undone for many speakers, however forms with mazuration are still dominant.

Vowels The change of initial ja-, ra- to je-, re-, still can be found in a few words: redzić (radzić).

Clear a sees its reflect as a, but the cluster -aj changes to -ej, except in the south-east, where aj changes to oj. This occurs most often in the imperative of verbs: dawejcie or in adverbial forms: dzisiej, wcorej, but south-east dzisioj, wcoroj. The nominal derivational suffix -aj generally changes to -oj or is kept as -aj. The change of ra- > re- is kept only in a few words: poredzić, redzić, redło, redlina, redlić, redlicka, rymie (standard ); other individual cases of this change are attested: taterok||tatarok, laterka||latarnio. The change of ja- > je- is exceedingly exceptional, seen in jerzymko (standard ), or jerzmo, przyjeciułka. Clear aN (with a nasal) remains unchanged in the whole region: kamiń, as well as in grammatical forms: zabrany, kijamy (standard ); the suffix -anin is reduces to -an: miescan (standard ).

The adverbs teraz, zaraz, chociaż, and nazad are realized as tero, zaro, chocioż, nazod.

Clear e generally corresponds with e.

Ablaut of e:o is missing in the words biedra, ûbier, zbier, piełón, pierón, Pietrz (regionally), piesnecki, mietła, pumietło, rzemiesło, wiesna, zwiesna, wietki, and wiesło; regionally zaciesane, Brzezoski; ablaut is present where it is missing in standard Polish in the words zyniaty (Standard Polish żonaty) siestrzyn. This is often the result of leveling: biere||bieróm, niese||niesóm, wynies (standard wyniósł), plete||pletóm||upletła, gniete, wywiezły, oblek. The terms źróbka (pronounced as źrubka), ziobro, Ziebroski||Ziobroski, ziomka (standard ziemia), kloryk (standard ), fajorki(||fajery), and arkusiorka show ablaut where it is absent in standard Polish. Ablaut can also be absent in the virile plural of passive adjectival participles via leveling to non-virile forms: napasuni (< napasóni). Soft 'e does not always show ablaut to 'a: wietrok||wiatrz, powiedać||powiadać, piesynka, piesnecka, nopletace, or 'a might not ablaut with 'e: bladsy, bladziyńki, bladziutki; po ciaście, lascyna, sianny (standard ). A change of 'e > 'o is absent in the words ôsieł, kozieł, kocieł.

The surname suffix -'owski and the toponym suffix -'ów are realized as -'ewski and -'ew; that is -e- is retained after soft consonants. The masculine dative singular ending -eji/-ewi can occur in both hard and soft stem nouns everywhere except in the north-east.

Mobile e can appear in some consonant clusters: wiater, meter||metra (standard ), or can become non-mobile in others: bes||besu (standard ||), dech||dechu (standard ||).

The cluster ej can raise in some words: ôlijander, klijeł, Macijeski, lecki (standard ). The infinitive ending -eć raises via leveling to -yć, -ić.

Similarly, or and ol can change to ur and ul but alternate with o: dochtur.

The high vowel u usually remains unchanged.

i, y change to e before r, l, ł: fieranka, derechtur, bielet, belica, mogieła, zmełka. This process also occurs in newer loanwords: pastelka. Exceptions to this change occur: wilk. The past tense of -ić/-yć verbs shows -el-, -eł- due to the same sound change (chodzieł, połozeła), except in Skierniewice County and neighboring regions, where in the masculine singular they take the ending -uł loaned from neighbouring, non-Księżak dialects. This ending can be seen especially if ł is realized as /w/.

The ending -ej raises to -y, -'i: blizy, ładni, wiyncy. This happens in the genitive-dative-locative feminine singular of adjectival declension.

In some words and in the imperative, the realization -ij keeps -j under influence of other cases and the present tense.

Latinate -yja/-ija words do not contract: Francyja||Francyjo.

Slanted vowels

Slanted á generally merges with o, but Halina Karaś notes that it is occasionally retained as á or sometimes merges with a due to influence from standard Polish; historically diphthongal /ɔu/ could be heard amongst some older women in the early 20th century, but generally o was and is much more common, and this diphthong amongst its users occurred only in open syllables. This o resulting from slanted á was sometimes prelabialized: môtoku ([mwɔtɔku], but the cluster -au- often diphthongizes to /ɔw/ noumyśnie ([nɔ͡umɘɕɲɛ])/noumyśle ([nɔ͡umɘɕlɛ]). This o resulting from á can appear in the stems of nouns: bol (standard ), before tautosyllabic voiced consonants: dziod||dziada, bobka (standard ).

The archaic genitive plural ending -∅ can cause slanting: lot||lata, dotychcos (standard )||cas (standard ).

The suffix -aj is realized as -oj: ûrodzoj||ûrodzoju, zwycoj||zwycoju, but can sometimes alternate with -a-: Gałoj||gałąja, Machoj||Machaja.

The suffixes/word-final clusters -ak, -as, -aszek, -al, -ar, -acz are realized as -ok, -os, -osek, -ol, -orz, -or (which sometimes alternates with -ar-, e.g. towor||toworu or towary), and -oc (rarely as . -ac) respectively. The adjectival ending -arski does not show slanting and is kept as -arski.

This o from á can be seen also in the nominative feminine singular of soft-stem nouns: groblo, but a can also be seen here; the suffix -nia is always realized as -nio but Latinate -yja/-ija nouns show fluctuation between -yjo/-ijo and -yja/-ija.

Neuter -ie gerunds take -o < -á in the genitive singular: godanio, and the nominative feminine singular of adjectives take -o: dzielno (standard ).

Contracted verbs show o < á (in turn < Proto-Slavic *VjV): grzoć sie, loć, sioć, śmioć sie, wioć; or can also appear not as the result of contraction: bocyć/bôcyć (standard ).

-am/-asz verbs show o: godos; broł (next to brała), but younger people show clear a in the masculine past sometimes: poprzedajał, widział. The imperative shows -oj in the south-east; the imperative dej is common everywhere.

The derivational prefix na- is often realized as no-: nocelnik, nolezy sie, but -a- can be seen" nawijać, naleźć/naliźć, similarly za- is often realized as zo-: zogun, but zopumoga next to zapoumoga.

The preposition za and zza is usually realized with clear a. The preposition dla can be realized as dla, dlo, or lo.

Some personal pronoun forms show o: jo, nos, wos, but ja and nas also occur.

Numerals formed with -naście or -nasty generally show -o-: jedynoście, jedynosty.