spiderlike vs arachnidian

spiderlike and arachnidian both are adjectives.

Word	Noun	Adjective	Verb	Adverb
spiderlike	No	Yes	No	No
arachnidian	No	Yes	No	No

As adjectives, spiderlike and arachnidian are synonyms defined as:

spiderlike and arachnidian: relating to or resembling a member of the class Arachnida

Other synonyms of spiderlike include arachnoid, spiderly, spidery.

spiderlike (adjective)	arachnidian (adjective)
relating to or resembling a member of the class Arachnida	relating to or resembling a member of the class Arachnida