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1. The quality of being enduring and free from change or variation
   "early mariners relied on the constancy of the trade winds";
   - stability
    
2. (psychology) the tendency for perceived objects to give rise to very similar perceptual experiences in spite of wide variations in the conditions of observation
   - perceptual constancy
    
3. Faithfulness and dependability in personal attachments (especially sexual fidelity)

Derived forms: constancies

See also: constant, inconstant

Type of: changelessness, faithfulness, fidelity, perception, unchangeability, unchangeableness, unchangingness

Encyclopedia: Constancy