say it: KIL-i-fish
killifish is a noun meaning "small mostly marine warm-water carp-like schooling fishes; used as bait or aquarium fishes or in mosquito control". It carries one recorded sense.
small mostly marine warm-water carp-like schooling fishes; used as bait or aquarium fishes or in mosquito control
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 killifish 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.