hot-work vs work on

hot-work and work on both are verbs.

Word	Noun	Adjective	Verb	Adverb
hot-work	No	No	Yes	No
work on	No	No	Yes	No

As verbs, work on is a hypernym of hot-work; that is, work on is a word with a broader meaning than hot-work:

Other hypernyms of hot-work include process, work.

hot-work (verb)	work on (verb)
roll, press, forge, or shape (metal) while hot	shape, form, or improve a material
	to exert effort in order to do, make, or perform something