de-icer vs ice melter

de-icer and ice melter both are nouns.

Word	Noun	Adjective	Verb	Adverb
de-icer	Yes	No	No	No
ice melter	Yes	No	No	No

As nouns, de-icer and ice melter are synonyms defined as:

de-icer and ice melter: a substance used to melt ice; it can take a form of liquid or solid crystals.

Other synonyms of de-icer include ice melt.

de-icer (noun)	ice melter (noun)
a substance used to melt ice; it can take a form of liquid or solid crystals.	a substance used to melt ice; it can take a form of liquid or solid crystals.