STABLE

adj. 1 steady, solid, firm, sound, sturdy, strong, durable, well-founded, fast, sure, established, deep-rooted, stout The building is designed to remain stable even in a severe earthquake 2 lasting, enduring, long-lasting, long-standing, secure, steadfast, steady, strong, unchanging, unchanged, unchangeable, unalterable, fixed, invariable, unwavering, immutable, permanent A stable relationship has existed between our countries for generations The relationship you and I enjoy has remained stable all our lives. 3 sane, (well-)balanced, responsible, reasonable, sensible, competent, accountable He seemed a nice, stable young man, and nobody would have guessed that he had a drugs habit