一月
ひとつき · hitotsuki · JLPT N5 · noun
calendar month
📅 一月 = one (hito) + month (tsuki): one month's duration
Read with native Japanese numbers: hito (one, as in hitotsu) + tsuki (month, moon). Same kanji read ichigatsu means January, so hitotsuki counts a span of time while ichigatsu names the calendar month.
一 — single horizontal stroke
一 is one of the simplest pictographs in Chinese, depicting a single horizontal line to represent the number one. It has retained essentially the same form since oracle bone script over 3,000 years ago. By extension it also means 'first,' 'whole,' or 'same.'
月 — pictograph of crescent moon
月 is a pictograph of a crescent moon, chosen over a full circle to distinguish it from 日 (sun). The inner strokes originally depicted the moon's shadow or markings. As a radical it often relates to the moon, time, or (via a lookalike form of 肉 'flesh') body parts.