四つ
よっつ · yottsu · JLPT N5 · noun
four (things)
🍀 yo (four) + ttsu (thing counter) = four things
Native Japanese counting: yo is the old word for four, and tsu is the general counter for things. The doubled t is just a small pause between them. Same yo as in yon (four) and yokka (the 4th day).
四 — enclosure 囗 + divide 八
Originally 四 was written as four horizontal strokes (亖), a simple tally for the number four. The current form, showing 八 (divide) inside an enclosure 囗, was borrowed during the Zhou dynasty and gradually replaced the older tally form. The shape is unrelated to its meaning today.