Boan (Buan, Ababuan) is a proposed intermediate group of Bantu languages coded Zones C and D in Guthrie's classification.McMaster, Mary Allen. 1988. Patterns of Interaction: A comparative ethnolinguistic perspective on the Uele region of Zaïre ca. 500 A.D. to 1900 A.D. Los Angeles: University of California. 346. There are three branches:
Komo (D20) Bali (D20), ?Beeke Bomokandian (the various Bwa and Biran languages) Biran (Bira–Amba) (D22, D30) Homa (Ngenda) (D40) Lika (D20) Bati–Angba (Bwa) (C40)
Beeke is an erstwhile member of the Nyali cluster that seems to be closest to Bali.
In the Glottolog 2.3 classification, several additional, poorly attested languages are included as being closest to Homa/Ngenda:
Bali (D20) Old Bomokandian Komoic (Biran, incl. Komo) Middle Bomokandian (Lika & Bati–Angba) Ngbele–Ngenda Extreme-north Vestigial-suffix Bantu: Kari, Ngbee, Nyanga-li (Gbati-ri) Ngendan Homa, Ngbinda, ?Boguru, ?Bodo (perhaps instead Lebonya)
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