Synonyms for constancy

noun

1. Faithfulness

   fidelity, attachment, adherence, fealty, allegiance, devotion, ardor, eagerness, zeal, passion, love, earnestness, steadfastness, permanence, staunchness, principle, integrity, honor, faith, honesty, devotedness, abidingness, endurance, dependability, trustworthiness, trustiness, unchangeableness, consistency, regularity, certainty, unfailingness; see also loyalty, reliability.

   Antonyms faithlessness, disloyalty*, perfidy.

2. Determination

   resolution, perseverance, doggedness, firmness; see determination 2.