愣
lèng · HSK 7
to stare blankly
heart radical 忄 + leng; sounds like length - you stare blankly the whole length of a moment
愣 (leng) pairs the heart/feeling radical 忄 with a sound part. Tie the reading to the English word length: distracted, you let the whole length of a moment slip by while staring blankly.
愣 — heart radical 忄 + 楞 (phonetic, simplified from 稜)
A semantic-phonetic compound: the heart radical 忄 signals a mental or emotional state, while 楞 supplies the sound. Originally meaning to be stunned or dazed, it extends to 'blank,' 'stupefied,' or 'rash,' as in 发愣 (to stare blankly).