六日
むいか · muika · JLPT N5 · noun
days
📅 六日 = six + day; mu (old native six) + ka (day counter) = muika
Days of the month use native Japanese numbers: mu is the old word for six (as in muttsu) and ka is the old counter for days. The i links them, giving mu-i-ka. Same pattern as futsuka (2nd) and mikka (3rd).
六 — top stroke 亠 + 八 (eight/split)
Originally a pictograph, possibly depicting a hut or shelter, but its early meaning was lost. It was borrowed phonetically to write the number 'six'. The modern form shows a top mark 亠 over 八, but this structure is not semantic — it's purely a loan character for the numeral.
日 — pictograph of the sun
日 is a pictograph of the sun, originally drawn as a circle with a dot or stroke inside representing the sun's substance. Over time the round shape was squared off into the modern rectangular form. It means 'sun' and by extension 'day'.