obstructer vs obstruction

obstructer and obstruction both are nouns.

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

As nouns, obstructer and obstruction are synonyms defined as:

Other synonyms of obstructer include impediment, impedimenta, obstructor.

obstructer (noun)	obstruction (noun)
any structure that makes progress difficult	getting in someone's way
someone who systematically obstructs some action that others want to take	the act of obstructing
	any structure that makes progress difficult
	something immaterial that stands in the way and must be circumvented or surmounted
	the physical condition of blocking or filling a passage with an obstruction