apt vs pertinent

apt and pertinent both are adjectives.

Word	Noun	Adjective	Verb	Adverb
apt	No	Yes	No	No
pertinent	No	Yes	No	No

As adjectives, apt and pertinent are synonyms defined as:

Other synonyms of apt include apposite.

apt (adjective)	pertinent (adjective)
being of striking appropriateness and pertinence	being of striking appropriateness and pertinence
(usually followed by `to') naturally disposed toward	having precise or logical relevance to the matter at hand
mentally quick and resourceful
at risk of or subject to experiencing something usually unpleasant