köken: */uwu/ → /uweru/ → /ueru/ From classical verb 飢う (uu). Development Natural progression from Old and Classical Japanese 下(しも)二(に)段(だん)活(かつ)用(よう) (shimo nidan katsuyō, “lower bigrade conjugation”) verbs ending in -u to modern Japanese 下(しも)一(いち)段(だん)活(かつ)用(よう) (shimo ichidan katsuyō, “lower monograde conjugation”) verbs ending in -eru.
đói (“hungry”) + meo; it is not clear if the second morpheme is really meo (“mold”) or not, although this word certainly influenced the creation of đói mốc đói meo.