obsessive
adjective
ob·ses·sive äb-ˈse-siv
əb-
1
a
: tending to cause obsession
b
: excessive often to an unreasonable degree
an obsessive interest
2
: of, relating to, or characterized by obsession : deriving from obsession
obsessive noun
obsessively adverb
obsessiveness noun
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Merriam-Webster unabridged



