"sweetheart, paramour, loved one" (archaic), c. 1200, lemman, "loved one of the opposite sex; paramour, lover; wife;" also "a spiritually beloved one; redeemed soul, believer in Christ; female saint devoted to chastity; God, Christ, the Virgin Mary;" also a term of intimate address to a friend or lover, contracted from late Old English leofman, a compound of leof "dear" (see lief) + man "human being, person" (from PIE root *man- (1) "man").
Originally of either gender, though in deliberate archaic usage it tends to be limited to women. Often in religious use in early Middle English, of brides of Christ, the spiritually beloved of God, etc.; by c. 1300 it could mean "betrothed lover," and by late 14c. it had the pejorative sense "concubine, mistress, gallant." For loss of medial -f-, compare had.
also freakout "bad psychedelic drug trip," or something comparable to one, 1966, from verbal phrase freak out, attested from 1965 in the drug sense (from 1902 in a sense "change, distort, come out of alignment"); see freak (n.). There is a coincidental appearance of the phrase in "Fanny Hill:"
She had had her freak out, and had pretty plentifully drowned her curiosity in a glut of pleasure .... [Cleland, "Memoirs of a Woman of Pleasure," 1749]
where the sense is "she had concluded her prank."