ἍΠΤΩ

ἅπτω, [ [in LXX chiefly for נגע;] ] prop., to fasten to; hence, of fire, to kindle, light: Lk 8:16 11:33 15:8, Ac 28:2. Mid., c. gen., to fasten oneself to, cling to, lay hold of (so in π.; MM, s.v.): Mt 8:3, 15, Jo 20:17, al.; of carnal intercourse, I Co 7:1; with reference to levitical and ceremonial prohibitions, II Co 6:17, Col 2:21; of hostile action, I Jo 5:18 (cf. ἀν-, καθ-, περι- άπτω).
SYN.: θιγγάνω, ψηλαφάω. ἅ. is the stronger, θ., to touch, the lighter term. ψ. is to feel, as in search of something (Tr., Syn., § xvii; Lft., Col., 201 f.).