welt vs work over

welt is a noun but work over is not a noun.

Word	Noun	Adjective	Verb	Adverb
welt	Yes	No	Yes	No
work over	No	No	Yes	No

As verbs, work over is a hypernym of welt; that is, work over is a word with a broader meaning than welt:

welt: beat severely with a whip or rod
work over: give a beating to; subject to a beating, either as a punishment or as an act of aggression

Other hypernyms of welt include beat, beat up.

welt (noun)	work over (noun)
a raised or strengthened seam
a raised mark on the skin (as produced by the blow of a whip); characteristic of many allergic reactions

welt (verb)	work over (verb)
put a welt on	give a beating to; subject to a beating, either as a punishment or as an act of aggression
beat severely with a whip or rod