押える
おさえる · osaeru · JLPT N3 · verb-ichidan
to restrain
✋ 押 = hand 扌 + shell 甲: a hand pressing down on a hard shell
Same kanji as 押す (osu, to push). Pushing turns into holding: osaeru is pushing on something until it stays put. Sound hook: osa-eru sounds like oh, stay here! Usually spelled 押さえる.
押 — hand radical 扌 + 甲 (jiǎ, phonetic)
押 is a semantic-phonetic compound. The hand radical 扌 supplies the meaning of pressing or holding down with the hand, while 甲 gives the sound. From the literal sense of pressing, it extended to signing/sealing documents, mortgaging, and detaining — all involving an authoritative 'pressing' action.