occlusion vs obstructer

occlusion and obstructer both are nouns.

Word	Noun	Adjective	Verb	Adverb
occlusion	Yes	No	No	No
obstructer	Yes	No	No	No

As nouns, obstructer is a hypernym of occlusion; that is, obstructer is a word with a broader meaning than occlusion:

Other hypernyms of occlusion include impediment, impedimenta, obstruction, obstructor.

occlusion (noun)	obstructer (noun)
the act of blocking	any structure that makes progress difficult
an obstruction in a pipe or tube	someone who systematically obstructs some action that others want to take
(dentistry) the normal spatial relation of the teeth when the jaws are closed
(meteorology) a composite front when colder air surrounds a mass of warm air and forces it aloft
closure or blockage (as of a blood vessel)