noun
nap; dozing off; sleeping while leaning on something
Refers to a short sleep, often while leaning on one's arm or an improvised support, rather than lying down properly. Common in literary or slightly old-fashioned contexts.
旅の途中、木にもたれて仮枕をした。
During the journey, I took a nap leaning against a tree.
彼は机に突っ伏して仮枕をとっている。
He is dozing off with his head on the desk.
昼寝 is a general afternoon nap, usually lying down. 仮枕 implies a more improvised, brief sleep, often not in a bed.
うたた寝 is dozing off unintentionally, often while sitting. 仮枕 is more deliberate, using something as a makeshift pillow.
Compound of 仮 (kari, 'temporary, makeshift') and 枕 (makura, 'pillow'). Literally 'makeshift pillow', extended to mean a nap taken using such an improvised support.