Grace
Middle English: via Old French from Latin gratia, from gratus ‘pleasing, thankful’; related to grateful.
wiktionary
From Middle English grace, from Old French grace (modern French grâce), from Latin grātia(“kindness, favour, esteem”), from grātus(“pleasing”), from Proto-Indo-European *gʷerH-(“to praise, welcome”); compare grateful.
The word displaced the native Middle English held, hield(“grace”) (from Old English held, hyld(“grace”)), Middle English este(“grace, favour, pleasure”) (from Old English ēste(“grace, kindness, favour”)), Middle English athmede(n)(“grace”) (from Old English ēadmēdu(“grace”)), Middle English are, ore(“grace, mercy, honour”) (from Old English ār(“honour, grace, kindness, mercy”)).
etymonline
grace (n.)
late 12c., "God's unmerited favor, love, or help," from Old French grace "pardon, divine grace, mercy; favor, thanks; elegance, virtue" (12c., Modern French grâce), from Latin gratia "favor, esteem, regard; pleasing quality, good will, gratitude" (source of Italian grazia, Spanish gracia; in Church use translating Greek kharisma), from gratus "pleasing, agreeable," from PIE *gwreto-, suffixed form of root *gwere- (2) "to favor."
Sense of "virtue" is early 14c., that of "beauty of form or movement, pleasing quality" is mid-14c. In classical sense, "one of the three sister goddesses (Latin Gratiæ, Greek Kharites), bestowers of beauty and charm," it is first recorded in English 1579 in Spenser. In music, "an embellishment not essential to the melody or harmony," 1650s. As the name of the short prayer that is said before or after a meal (early 13c.; until 16c. usually graces) it has a sense of "gratitude." As a title of honor, c. 1500.
Grace
fem. proper name, literally "favor, grace;" see grace (n.).
grace (v.)
c. 1200, "to thank," from Old French graciier "thank, give thanks to; praise," from grace "mercy, favor, thanks, virtue" (see grace (n.)). Meaning "to show favor" (mid-15c.) led to that of "to lend or add grace to something" (1580s, as in grace us with your presence), which is the root of the musical sense in grace notes (1650s). Related: Graced; gracing.
