Invariable vs. Invariant

Not variable; unalterable; uniform; always having the same value.

(math) Constant.

That cannot undergo inflection, conjugation or declension.

Example: ‘The French adjective marron (brown) is invariable: it does not take the usual s in the plural.’;

Something that does not vary; a constant.

Not given to variation or change; unalterable; unchangeable; always uniform.

Example: ‘Physical laws which are invariable.’;

An invariable quantity; a constant.

not liable to or capable of change;

Example: ‘an invariable temperature’; ‘an invariable rule’; ‘his invariable courtesy’;

not varying; constant

(mathematics) Unaffected by a specified operation (especially by a transformation)

Neither covariant nor contravariant.

An invariant quantity, function etc.

An invariable quantity; specifically, a function of the coefficients of one or more forms, which remains unaltered, when these undergo suitable linear transformations.

unaffected by a designated operation or transformation

persistent in occurrence and unvarying in nature;

Example: ‘maintained a constant temperature’; ‘a constant beat’; ‘principles of unvarying validity’; ‘a steady breeze’;