threadlike vs filiform

threadlike and filiform both are adjectives.

Word	Noun	Adjective	Verb	Adverb
threadlike	No	Yes	No	No
filiform	No	Yes	No	No

As adjectives, threadlike and filiform are synonyms defined as:

Other synonyms of threadlike include filamentlike, filamentous, thready.

threadlike (adjective)	filiform (adjective)
thin in diameter; resembling a thread	thin in diameter; resembling a thread