An abnormality; a departure: "Vice was a deviation from our nature"(Henry Fielding).
Deviant behavior or attitudes.
Divergence from an accepted political policy or party line.
Deflection of a compass needle caused by local magnetic influence, especially on a ship.
Statistics The difference, especially the absolute difference, between one number in a set and the mean of the set.
de'vi·a'tion·ism n., de'vi·a'tion·ist adj. & n.
Synonyms: These nouns mean a departure from what is prescribed or expected: tolerates no deviation from the rules; regretted the aberrations of my adolescence; the divergence of two cultures.