felicity (n.) Look up felicity at Dictionary.com
late 14c., "happiness; that which is a source of happiness," from Old French felicite "happiness" (14c.), from Latin felicitatem (nominative felicitas) "happiness, fertility," from felix (genitive felicis) "happy, fortunate, fruitful, fertile," from Latin root *fe-, equivalent of PIE *dhe(i)- "to suck, suckle, produce, yield" (see fecund). Meaning "skillful adroitness, admirable propriety" is from c.1600.