association vs ecology

association and ecology both are nouns.

Word	Noun	Adjective	Verb	Adverb
association	Yes	No	No	No
ecology	Yes	No	No	No

association (noun)	ecology (noun)
the act of consorting with or joining with others	the branch of biology concerned with the relations between organisms and their environment
the process of bringing ideas or events together in memory or imagination	the environment as it relates to living organisms
a formal organization of people or groups of people
(ecology) a group of organisms (plants and animals) that live together in a certain geographical region and constitute a community with a few dominant species
(chemistry) any process of combination (especially in solution) that depends on relatively weak chemical bonding
a relation resulting from interaction or dependence
a social or business relationship
the state of being connected together as in memory or imagination