cubicular

Etymology tree Proto-Italic *kubāō Latin cubō Latin -i- Proto-Indo-European *-tḗr Proto-Indo-European *-trom Proto-Indo-European *-tlom Proto-Italic *-klom Latin -culum Latin cubiculum Proto-Indo-European *h₂el-der.? Proto-Italic *-ālis Latin -ālis Latin -āris Latin cubiculārislbor. English cubicular Learned borrowing from Latin cubiculāris (“relating to a bedroom”), from cubiculum (“small bedroom, bedchamber”) + -āris (“suffix meaning ‘of or pertaining’ to forming adjectives”). Cubiculum is derived from cubāre (the present active infinitive of cubō (“to lie down, recline; to sleep”), possibly ultimately from Proto-Indo-European *ḱewb-) + -i- (interfix used between stems and suffixes) + -culum (an inflected form of -culus, a variant of -ulus (diminutive suffix)). Compare Middle English cubiculer (“servant working in a chamber, chamberlain”).

来源：wiktionary