Other forms: dented, dents, denting
A dent is the hollow left in a hard surface where something hit it. The metal is pushed in but not broken.
Cars collect them and so do tins and kettles. The verb goes with it, so a wing gets dented in a car park. The figurative sense is about reduction, and making a dent in a pile of work or a debt means reducing it noticeably, while denting somebody's confidence means damaging it. Both come from the same picture of something pushed inwards without breaking.
A dent is a blow. Old English dynt meant the strike itself, and also the mark and the noise it made, which is why dent and dint turn out to be one word twice over.
Proto-Germanic
*duntiz — a blow
Old English
dynt — blow, strike, the mark or noise of a blow
Middle English
dent
English, today
dent
Built from
From Middle English dent, dente, dint (“a blow; strike; dent”), from Old English dynt (“blow, strike, the mark or noise of a blow”), from Proto-Germanic duntiz (“a blow”). Akin to Old Norse dyntr (“dint”). a doublet of dint.
Etymology from Wiktionary, CC BY-SA