别
bié · HSK 1
don't
🚫 别 = 另 (other) + 刂 (knife): cut apart → separate → 'don't'
Original sense was to divide or separate with a blade, hence the 刂 knife radical on the right. The 'don't / do not' meaning grew from 'set apart, keep away from' — telling someone to stay separate from an action.
别 — separate (knife 刂 + 另 phonetic/'other')
别 originally depicted using a knife (刂) to separate flesh from bone, giving the core sense of 'divide' or 'part from'. The left component 另 ('another, other') reinforces the idea of setting things apart and also hints at the sound. From 'separate' the meaning naturally extended to 'other, different' and to the adverb 'don't' (i.e. do otherwise).