足袋
たび · tabi · JLPT N3 · noun
sock
🧦 足袋 = foot + bag: a cloth bag for the foot
足 means foot and 袋 (ふくろ) means bag or pouch, so the word is literally a foot bag. The kanji are read together as tabi, not by their usual readings. The split toe means the sock fits a thong sandal such as zōri or geta.
足 — top 口 (mouth/enclosure) + bottom 止 (foot)
Originally a pictograph of a leg and foot, with the upper square representing the knee or shin and the lower part 止 depicting the foot itself. It primarily means 'foot' and by extension 'sufficient' or 'enough,' a meaning shift likely from the idea of standing firmly or having a solid footing.
袋 — 代 (dài, phonetic) + 衣 (clothing)
袋 is a semantic-phonetic compound. The bottom 衣 'clothing/cloth' gives the meaning, since bags were originally made of cloth, while 代 on top supplies the sound 'dài'. It has long meant 'bag, sack, pouch'.