睚 (yá): corner of the eye

Meanings

他睚眦必报，毫不宽容。

Tā yázìbìbào, háobù kuānróng.

He repays the smallest grudge without fail.

睚眦之怨也必报。

Yá zì zhī yuàn yě bì bào.

Even a glare of resentment is repaid.

history

Lives mainly in 睚眦必报, from the 史记 (Records of the Grand Historian): to avenge even a hostile glance, meaning extremely vindictive.

radical

目 mù

eye

The eye radical sets the literal sense: 睚 is the corner of the eye, and by extension the angry look that flashes there.

phonetic

厓 yá

cliff edge

Supplies the reading yá; its sense of an edge faintly echoes the "corner" of the eye, though it works mainly as the sound.

睚 yá