secure vs insure

secure is an adjective but insure is not an adjective.

Word	Noun	Adjective	Verb	Adverb
secure	No	Yes	Yes	No
insure	No	No	Yes	No

As verbs, secure and insure are synonyms defined as:

Other synonyms of secure include assure, ensure, guarantee.

secure (adjective)	insure (adjective)
free from fear or doubt; easy in mind
free from danger or risk
not likely to fail or give way
immune to attack; incapable of being tampered with
financially safe

secure (verb)	insure (verb)
make certain of	be careful or certain to do something; make certain of something
cause to be firmly attached	protect by insurance
fill or close tightly with or as if with a plug	make certain of
furnish with battens	take out insurance for
get by special effort
assure payment of