(Main list of acronyms)
__NOTOC__ y – (s) Yocto- Y – (s) Yotta – Yttrium
Y0–9 Y2K – (i) Year Two Thousand
YA yA – (s) Yoctoampere Ya – (s) Yottayear YA (s) Yottaampere (i) Young Adult YAC – (a/i) Youth-Adult Committee YAFLA – (a) Yet Another Five Letter Abbreviation YAP – (a) Young Aspiring Professional YaBPr – (a) Yet another Brother Pat rant YABSLAG – (a) Yet another boy singing like a girl
YB Yb – (s) Ytterbium YB – (i) Youcef Benzouada (Southern Algerian name)
YC yC – (s) Yoctocoulomb YC – (s) Yottacoulomb
YD YD – (s) People's Democratic Republic of Yemen (ISO 3166 digram, obsolete 1990) YDS – (i) Yosemite Decimal System (climbing)
YE YE – (s) Yemen (ISO 3166 digram) YEM – (s) Yemen (ISO 3166 trigram) – Manitowaning/Manitoulin East Municipal Airport IATA airport code YER – (s) Yemeni rial (ISO 4217 currency code)
YF yF – (s) Yoctofarad YF – (s) Yottafarad
YG yg – (s) Yoctogram Yg – (s) Yottagram YGM – You've got mail Ygo – (i) Yu-Gi-Oh! YGCO – (i) Yamaneko Group of Comet Observers
YH yH – (s) Yoctohenry YH – (s) Yottahenry YHS – Ya Hoor sur! YHBT – (i) You Have Been Trolled YHIH1 – (a) You Heard It Here First (lowercase: yhih1, pronounced yi-hi) YHII – You Have It Inside
YI yi – (s) Yiddish language (ISO 639-1 code) Yi – (s) Yobi YI – (s) Serbia and Montenegro (deprecated FIPS 10-4 country code, now RB (Serbia) and MJ (Montenegro)) yid – (s) Yiddish language (ISO 639-2 code) YIH – (a) Yiff In Hell YILP – (a) Youth Integration Livelihood Improvement Project Yippie – (p) Youth International Party + suffix
YJ yJ – (s) Yoctojoule YJ – (s) Yottajoule
YK yK – (s) Yoctokelvin YK – (s) Yottakelvin YKYFCW – You know you're from Christchurch when (post-earthquake joke)
YL yL – (s) Yoctolitre YL – (s) Yottalitre
YM ym – (s) Yoctometre Ym – (s) Yottametre YM – (s) Yemen (FIPS 10-4 country code) – (i) Your Magazine (originally Young Miss, later Young & Modern) YMCA – (i) Young Men's Christian Association YMD – (s) People's Democratic Republic of Yemen (ISO 3166 trigram, obsolete 1990) YMMD – (i) You Make My Day YMMV – (i) Your Mileage May Vary (adapted from the EPA's automobile mileage estimates, where it is used to convey the original meaning, "results may vary"); but (now) when used as an idiom, it -- (either the acronym "YMMV" or the 4 words) -- can instead mean (this e.g. comes from wikt:your mileage may vary#Phrase:) "this is just my opinion, your opinion may be different".
YN yN – (s) Yoctonewton YN – (s) Yottanewton YNWA – reference to Liverpool F.C.'s sports anthem, the 1945 show tune You'll Never Walk Alone
YO yo – (s) Yoruba language (ISO 639-1 code) YO – (s) former Yugoslavia (NATO country code, obsolete 1993) YOLO – (a) You Only Live Once yor – (s) Yoruba language (ISO 639-2 code)
YP YPA – (i) Yards per Pass Attempt (football statistic) YPG – (i) Yekîneyên Parastina Gel (Kurdish, "People's Protection Units" or "People's Defense Units") YPIO – (a) Your Problem Is Obvious YPO – (a) Young Presidents' Organization
YR YRR – (i) "Young, Restless, and Reformed", an alternative name for the New Calvinist movement
YS ys – (s) Yoctosecond yS – (s) Yoctosiemens Ys – (s) Yottasecond YS – (s) Yottasiemens YSA (i) Young Single Adult, a designation used by the LDS Church for single adults under 30 Young Socialist Alliance Youth Service America
YT yT – (s) Yoctotesla YT (s) Mayotte (ISO 3166 digram) Yottatesla Yukon Territory (postal symbol) YTD – (i) Year-To-Date YTM – (i) Yield to Maturity YTS – (i) Youth Training Scheme YTT – Yoshi Topsy-Turvy YT – YouTube
YU YU (i) York University (s) former Yugoslavia (ISO 3166 digram, obsolete 2003) YUG – (s) former Yugoslavia (ISO 3166 trigram, obsolete 2003) Yuppie – (p) Young Urban Professional + suffix
YV yV – (s) Yoctovolt YV – (s) Yottavolt
YW yW – (s) Yoctowatt YW – (s) Yottawatt YWCA – (i) Young Women's Christian Association YWMV – (i) Your Wallet May Vary (to convey "our budgets are different as far as what is affordable / justifiable")
YY YYH (i) YuYu Hakusho (s) Taloyoak Airport, IATA airport code YYK – (i) Yeah you know
YZ