1590s, "dedicated or given in fulfillment of a vow," from French votif, from Latin votivus "of or pertaining to a vow, promised by a vow, conforming to one's wishes," from votum (see vow (n.)).
c. 1200, devocioun, "profound religious emotion, awe, reverence," from Old French devocion "devotion, piety" and directly from Latin devotionem (nominative devotio), noun of action from past-participle stem of devovere "dedicate by a vow, sacrifice oneself, promise solemnly," from de "down, away" (see de-) + vovere "to vow" (see vow (n.)). From late 14c. as "an act of religious worship, a religious exercise" (now usually devotions).
In ancient Latin, "act of consecrating by a vow," also "loyalty, fealty, allegiance;" in Church Latin, "devotion to God, piety." The application to secular situations came to English via Italian and French; sense of "act of setting apart or consecrating" is from c. 1500.
1580s, "appropriate by or as if by vow," from Latin devotus, past participle of devovere "dedicate by a vow, sacrifice oneself, promise solemnly," from de "down, away" (see de-) + vovere "to vow" (see vow (n.)). From c. 1600 as "apply zealously or exclusively." From 1640s as "to doom, consign to some harm or evil," and the word commonly had a negative sense in 18c.: The second and third meanings in Johnson's Dictionary (1755) are "to addict, to give up to ill" and "to curse, to execrate; to doom to destruction." Related: Devoted; devoting.
To devote indicates the inward act, state, or feeling; to dedicate is to set apart by a promise, and indicates primarily an external act; to consecrate is to make sacred, and refers to an act affecting the use or relations of the thing consecrated .... [Century Dictionary]
c. 1200, of persons, "yielding reverential devotion to God," especially in prayer, "pious, religious," from Old French devot "pious, devoted, assiduous" (Modern French dévot) and directly from Latin devotus "given up by vow, devoted" (source also of Spanish and Portuguese devoto), past participle of devovere "dedicate by vow" (see devotion). Of actions, "expressing devotion or piety," late 14c. Meaning "sincere, solemn" is from mid-15c. Related: Devoutly; devoutness.