solder vs soft-solder

solder is a noun but soft-solder is not a noun.

Word	Noun	Adjective	Verb	Adverb
solder	Yes	No	Yes	No
soft-solder	No	No	Yes	No

As verbs, soft-solder is a hyponym of solder; that is, soft-solder is a word with a more specific, narrower meaning than solder:

Other hyponyms of solder include dip solder, braze.

solder (noun)	soft-solder (noun)
an alloy (usually of lead and tin) used when melted to join two metal surfaces

solder (verb)	soft-solder (verb)
join or fuse with solder	repair with soft-solder