Entry Word: unstable

Function: adjective

Meaning: 1 not being in or able to maintain a state of balance <when we put the books down on the unstable desk, the whole stack went crashing to the floor>

Synonyms unbalanced, unsteady

Related Words rickety, shaky, tottery, wobbly; cockeyed, lopsided, uneven

Near Antonyms even, level, straight; sound, sturdy, substantial

Antonyms balanced, stable, steady

2 likely to change frequently, suddenly, or unexpectedly <financial investors donʼt like an unstable economy> — see fickle 1
3 not staying constant <unstable temperatures are not ideal storage conditions for wine> — see uneven 2