Remaining the same; not altering or varying over time.
From Middle English, combining the prefix 'un-' (not) with 'changing' from Old French 'changier'. The concept evolved from describing physical constancy to abstract permanence.
This word captures humanity's deep fascination with permanence in an impermanent world. Interestingly, the only truly unchanging thing in the universe might be change itself, making this word philosophically paradoxical.
Complete word intelligence in one call. Free tier — 50 lookups/day.