Antonyms of adj unfluctuating

1 sense of unfluctuating

Sense 1
firm, steady, unfluctuating -- (not liable to fluctuate or especially to fall; "stocks are still firm")

INDIRECT (VIA stable) -> unstable -- (lacking stability or fixity or firmness; "unstable political conditions"; "the tower proved to be unstable in the high wind"; "an unstable world economy")

Similarity of adj unfluctuating

1 sense of unfluctuating

Sense 1
firm, steady, unfluctuating -- (not liable to fluctuate or especially to fall; "stocks are still firm")
       => stable (vs. unstable) -- (resistant to change of position or condition; "a stable ladder"; "a stable peace"; "a stable relationship"; "stable prices")