constancy has definitions from the fields of sexuality,psychology
1
[ noun ] the quality of being free from change or variation

Synonyms

stability

Used in print

(Frederick Mosteller et al., Probability with...)

The constancy of p and the independence are the conditions most likely to give trouble in_practice .

2
[ noun ] (psychology) the tendency for perceived objects to give rise to very similar perceptual experiences in spite of wide variations in the conditions of observation
3
[ noun ] (sexuality) faithfulness in personal attachment (especially sexual fidelity)

Related terms

fidelity

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