say it: kuhm-PLAY-suhn-see
complacency is a noun meaning "the feeling you have when you are satisfied with yourself". It carries one recorded sense.
the feeling you have when you are satisfied with yourself
“his complacency was absolutely disgusting”
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for complacency come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.