say it: pree-VEN-tuh-tiv
preventative is a noun and adjective meaning "remedy that prevents or slows the course of an illness or disease". It carries 5 recorded senses.
remedy that prevents or slows the course of an illness or disease
“the doctor recommended several preventatives”
any obstruction that impedes or is burdensome
an agent or device intended to prevent conception
tending to prevent or hinder
preventing or contributing to the prevention of disease
“preventive medicine”
“vaccines are prophylactic”
“a prophylactic drug”
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 preventative 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.