verb (used without object), fluc·tu·at·ed, fluc·tu·at·ing.
- to change continually; shift back and forth; vary irregularly: The price of gold fluctuated wildly last month.
- to move back and forth in waves.
verb (used with object), fluc·tu·at·ed, fluc·tu·at·ing.
- to cause to fluctuate.
- to change or cause to change position constantly; be or make unstable; waver or vary
- (intr) to rise and fall like a wave; undulate
1630s, from Latin fluctuatus, past participle of fluctuare “to undulate” (see fluctuation). Related: Fluctuated; fluctuates; fluctuating.