Quick Definition
κρούω v. I knock
Strong's Definition
apparently a primary verb; to rap
KJV Usage: knock
UBS Dictionary of the Greek New Testament
verb
19.12 · Physical Impact · Hit, Strike
to knock to knock on a door, as a means of signaling one’s presence to those inside A literal rendering of κρούω in MAT 7:7 may be misleading in a number of languages, since in some areas only thieves knock on doors. This is done in order to determine whether anyone is at home, in which case, of course, the thief runs off. The more general practice for signaling one’s presence may be to cough, to clap the hands, or to call out one’s name.
MAT 7:7 · MAT 7:8 · LUK 11:9 · LUK 11:10 · LUK 12:36 · LUK 13:25 · ACT 12:13 · ACT 12:16 · REV 3:20
1 MAT 7:7 In view of the fact that κρούω in MAT 7:7 involves an act of communication, it would be possible to classify this meaning of κρούω in Domain 33 Communication, but since the action of κρούω involves physical impact, it is listed here in Domain 19.
UBS Dictionary of the Greek New Testament © United Bible Societies, licensed CC BY-SA 4.0.
Mounce Concise Greek Dictionary
κρούω krouō 9x
to knock at a door, Mt. 7:7, 8; Lk. 11:9, 10; 12:36; 13:25; Acts 12:13, 16; Rev. 3:20*
Abbott-Smith Greek Lexicon
κρούω,
[in LXX: seq. ἐπί, Jg 19:22, Ca 5:2 (דִפק);] c, acc., τ. αὐλαίαν, Jth 14:14*;]
to strike, knock: at a door (κόπτειν, in Att.), Mt 7:7, 8, Lk 11:9, 10 12:36, Ac 12:16, Re 3:20; c. acc., τ. θύραν, Lk 13:25, Ac 12:13.†
Moulton & Milligan — Vocabulary of the Greek NT
κρούω. For this verb of ‘‘ knocking” at the door, as in Lk τ 355, Ac 1213, where the Purists would have preferred κόπτω (cf. Lob. Phryn. p. 177f.), see P Par 507 (B.c. 160) εἶδον Tirohepatov . . . Kpovfovta] θύραν. Other exx. of this usage in late Greek are given in Field Wo/es, p. 120. In the magic P Lond 46” (iv/a.p.) (=I. p. 67) we have— Kpove εἰς τὸ οὖς λέγων KTA. For the subst. Kpodpa see BGU IV. 11254, 31 (B.c. 13), and for the compd. ἐκκρούω in the sense of ** put off,” “‘evade,”’ cf. P Fay 109° (early i/a.D.) Σέλευκος γάρ μου αὐτοὺς ὧδε ἐκκ[έκ]ρουκε λέγων ὅτι συνέστακας ἑαυτῶι, ““ Seleucus has evaded paying the money by saying that you have made an arrangement with him (to pay instead) ” (Edd.).
Liddell-Scott-Jones — Greek-English Lexicon
κρούω (krouō) — to knock. κρούω, future -σω [Refs 5th c.BC+]: aorist [Refs 6th c.BC+]: perfect [Refs 5th c.BC+] —middle, aorist [Refs 5th c.BC+]:—passive, aorist [Refs 3rd c.BC+]: perfect κέκρουμαι (ἀπο-) [Refs 5th c.BC+]:—strike, smite, [Refs 5th c.BC+]; κρούσας δὲ πλευρὰ [τῶν ἵππων] [Refs 5th c.BC+]; also εἰς τὴν χεῖρα τοῖς δακτύλοις κ. with the fingers, [Refs 2nd c.AD+] tickles, [Refs 4th c.BC+]
2. strike one against another, strike together, κ. χεῖρας clap the hands, [Refs 6th c.BC+] [same place]: metaphorically, ἀλλήλων τοὺς λόγους τοῖς λόγοις ἐκρούομεν ἄν would have knocked their heads together, [Refs 5th c.BC+]
3. κ. πόδα (i.e. κ. τὴν γῆν τῷ ποδί), in dancing, [Refs 5th c.BC+] (Lyric poetry).
4. metaphorically from tapping an earthen vessel, to try whether it rings sound (compare [Refs]: examine, try, prove, [Refs 6th c.BC+]; κἂν διαπειρώμενος κρούσῃς [τὸν κόλακα] [Refs 1st c.AD+]
5. strike a stringed instrument with a plectron, [Refs 5th c.BC+]: generally, play any instrument (see. κροῦμα, κρουματικός) [Refs]: with dative, κ. κρεμβάλοις, ={κρεμβαλίζειν}, [Refs 2nd c.AD+]
6. κ. τὴν θύραν knock at the door on the outside, [LXX+5th c.BC+].
7. κ. σταθμὸν ἑτερόζυγον, ={κρουσιμετρέω}, [Refs 5th c.BC+].
8. obscene meaning, [Refs 5th c.BC+].
9. middle, κρούεσθαι πρύμναν back water, [Refs 5th c.BC+] (also in active, [Refs 2nd c.BC+]: hence κρούεσθαι τὸ πτερόν fly backwards, [Refs 2nd c.AD+] —also in active, [Refs 3rd c.AD+]
10. κρούειν ἀκράτῳ, see at {πατάσσω} [Refs]