Not subject to change; remaining the same; constant, permanent, or eternal.
From 'change' plus '-less' suffix (from Old English '-leas'). The '-less' suffix means 'without,' creating an antonym of 'changeful' with a more Latinate feel despite Germanic roots.
Poets and philosophers love 'changeless' when describing eternal things—'the changeless stars,' 'changeless truth'—because the word creates a sense of gravitas and permanence that a simple 'unchanging' can't quite match, showing how suffix choice affects emotional tone.
Complete word intelligence in one call. Free tier — 50 lookups/day.