in·var·i·ant 
(ĭn-vârē-ənt)
(ĭn-vârē-ənt)adj.
1. Not varying; constant.
2. Mathematics Unaffected by a designated operation, as a transformation of coordinates.
n.
An invariant quantity, function, configuration, or system.
- funambulism
- funambulist
- function
- functional
- functional food
- functional group
- functional illiterate
- functionalism
- functional isomer
- functionalist
- functionality
- functionally
- functional magnetic resonance imaging
- functional neurological symptom disorder
- functional shift
- functionary
- function key
- functionless
- function word
- functor
- fund
- fundament
- fundamental
- fundamental fermion
- fundamental force