Meaning : Not subject or susceptible to change or variation in form or quality or nature.
Example :
The view of that time was that all species were immutable, created by God.
Synonyms : immutable
Capable of or tending to change in form or quality or nature.
A mutable substance.Meaning : Remaining the same for indefinitely long times.
Synonyms : unalterable
Changeless meaning in Bengali (Bangla).