利害
lì hai · HSK 7
terrible
⚖️ 利 profit + 害 harm = the upside and the downside together
利 means benefit or gain; 害 means harm or damage. Stack the two opposites and you get the gains and losses, the pros and cons. The same two characters (often as 厉害) also flip to mean terrible or formidable.
利 — grain 禾 + knife 刂
Originally a pictograph showing a knife (刂) cutting grain (禾), depicting harvest. From the idea of a sharp blade reaping crops, it extended to mean 'sharp,' then 'benefit,' 'profit,' or 'advantage' — the gain that comes from a successful harvest.
害 — 宀 roof + 丯 (phonetic) + 口 mouth
Originally an ideograph showing harm spoken under a roof, with 宀 (roof/house) on top, a phonetic element 丯 in the middle, and 口 (mouth) below suggesting harmful speech. Over time it shifted from 'injury caused by words' to the broader senses of 'harm,' 'injure,' and 'fear.'