say it: AHR-pee-em
rpm is a noun meaning "rate of revolution of a motor". It carries one recorded sense.
rate of revolution of a motor
“the engine was doing 6000 revs”
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 rpm 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.