nearly half a day; about half a day
Used to describe a duration of roughly half a day, often in narrative or descriptive contexts. Can function as a noun or adverbially.
小半日ほど待ったが、彼は現れなかった。
I waited for nearly half a day, but he didn't show up.
We walked the mountain trail for about half a day.
Compound of 小 (ko, 'small') + 半日 (hannichi, 'half a day'), literally 'a small half-day', indicating a duration close to but not quite half a day.