指差す
ゆびさす · yubisasu · JLPT N1 · verb-godan
to point at
👉 指 (finger) + 差す (thrust/insert): thrust a finger out to point at something
指差す is literally 'finger-thrust': 指 means finger and 差す means to thrust or stick out. Sounds like 'you-bee-sasu': 'You be sass-u' and point at the one who's sassy.
指 — hand radical 扌 + 旨 (zhǐ, phonetic)
指 is a semantic-phonetic compound. The hand radical 扌 gives the meaning — something done with the hand, namely pointing with a finger. 旨 supplies the sound 'zhǐ'. From 'finger' it naturally extended to the verb 'to point' and figurative senses like 'to indicate' or 'to refer to'.
差 — 垂 (drooping) + 工 (work/tool)
Originally depicted a hand reaching down to grasp grain stalks of uneven length, suggesting discrepancy or unevenness. From this came the meaning 'difference' or 'to differ.' The reading chā specifically carries the sense of disparity, while other readings developed meanings like 'to dispatch' (chāi) and 'poor/lacking' (chà).