The phrase "was variable" suggests that something is subject to change or inconsistency. The antonyms for this term would include "steady," "constant," "consistent," and "uniform." These words indicate that something is reliable, unwavering, and consistent in its behavior or performance. Other antonyms for "was variable" might include words like "predictable," "regular," and "fixed," suggesting that something follows a stable pattern or routine. Ultimately, the antonyms for "was variable" describe the opposite of fluctuation and instability, implying that something is trustworthy, dependable, and constant.