scar

Middle English scar blended two separate words: escare, a scab, traced back through Old French and Late Latin to Greek eskhára, 'scab left from a burn'; and skar, meaning an incision or fissure, from Old Norse skarð, 'notch, gap.'

These two threads — the healed burn and the raw cut — merged in Middle English into one word for a lasting mark on skin, quietly pushing out the older native English terms dolg and wundswaþu.

It's a doublet of eschar, the medical term for scab tissue, and shares deeper roots with shard through the Old Norse and Old English words for a notch or broken fragment.