con·stan·cy 
/ˈkɑ:nstənsi/ noun
/ˈkɑ:nstənsi/ noun [noncount] formal 1 : the quality of staying the same : lack of change
▪ the constancy of the Earth's rotation ▪ maintaining constancy of speed 2 : the quality of being loyal to a person or belief
▪ There was no doubt of his constancy [=fidelity] to his wife.
▪ the constancy of the Earth's rotation ▪ maintaining constancy of speed
▪ There was no doubt of his constancy [=fidelity] to his wife.
