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Definitions

momentary

[moh-muhn-ter-ee] / ˈmoʊ mənˌtɛr i /
ADJECTIVE
brief, fleeting
Synonyms
STRONGEST
short-lived temporary transitory
WEAK
cursory dreamlike ephemeral evanescent flashing flitting flying fugacious fugitive gone in flash hasty impermanent impulsive in wink of an eye instantaneous like lightning passing quick shifting short spasmodic summary transient vanishing volatile
Antonyms
STRONGEST
lasting lengthy long-lived permanent
WEAK
long-lasting staying

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.