1. rise and fall irregularly in number or amount:"trade with other countries tends to fluctuate from year to year"Similarvarydiffershiftchangealterwaverswingoscillatealternaterise and fallgo up and downsee-sawyo-yobe unstablebe unsteadyOppositebe steady
Word Originmid 17th century (earlier (late Middle English) as fluctuation): from Latin fluctuat- ‘undulated’, from the verb fluctuare, from fluctus ‘flow, current, wave’, from fluere ‘to flow’.