say it: rel-uh-TIV-uh-tee
relativity is a noun meaning "(physics) the theory that space and time are relative concepts rather than absolute concepts". It carries 2 recorded senses.
(physics) the theory that space and time are relative concepts rather than absolute concepts
physics
the quality of being relative and having significance only in relation to something else
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 relativity 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.