A.“ἔκρουσα” X.An.4.5.18, Hyp.Fr. 201: pf. “κέκρουκα” Diogenian.3.38, (ἐκ-) Pl.Phdr.228e, (προς-) D.21.206:—Med., aor. “ἐκρουσάμην” Th.7.40:—Pass., aor. “ἐκρούσθην” Eratosth. Cat.32: pf. κέκρουμαι (ἀπο-) X.HG7.4.26, or -ουσμαι (ἀπο-) Ar.Ach.459:—strike, smite, “ῥυτῆρι κ. γλουτόν” S.Fr.501; κρούσας δὲ πλευρὰ [τῶν ἵππων] E.Fr.779.6; “τὸν λυχνοῦχον” Lys.Fr.83; “τοῖς ποσὶ τὴν γῆν” Arr.An.7.1.5; also εἰς τὴν χεῖρα τοῖς δακτύλοις κ. with the fingers, D.C.40.16: metaph., κνῖσα κ. ῥινὸς ὑπεροχάς tickles, Ephipp. 3.3.
2. strike one against another, strike together, κ. χεῖρας clap the hands, E.Supp.720; “τὰ ὅπλα κρουόμενα πρὸς ἄλληλα” Th.3.22; “τὰς ἀσπίδας πρὸς τὰ δόρατα” X.An. l.c.: metaph., ἀλλήλων τοὺς λόγους τοῖς λόγοις ἐκρούομεν ἄν would have knocked their heads together, Pl.Tht.154e.
3. κ. πόδα (i.e. κ. τὴν γῆν τῷ ποδί), in dancing, E.El. l.c. (lyr.); “ἴχνος ἐν γᾷ κ.” Id.IA1043 (lyr.).
4. metaph. from tapping an earthen vessel, to try whether it rings sound (cf. “κροῦσις” 2): examine, try, prove, “κρούετε ἀπολαμβάνοντες τὸ καλόν” Pl.Hp.Ma.301b; κἂν διαπειρώμενος κρούσῃς [τὸν κόλακα] Plu.2.64d.
5. strike a stringed instrument with a plectron, Simon.183, Pl.Ly.209b: generally, play any instrument (v. κροῦμα, κρουματικός)“, αὐλεῖ . . κρούων ἰαστί” Com.Adesp.415: c. dat., κ. κρεμβάλοις, = κρεμβαλίζειν, Ath.14.636d.
6. κ. τὴν θύραν knock at the door on the outside, Ar.Ec.317, 990 (with play on signf. 8), X.Smp.1.11, Pl.Prt.310b, 314d, etc.; κόπτειν is better Att.acc.to Phryn.154; later “κ. ἐπὶ τὴν θύραν” LXX Jd.19.22.
7. κ. σταθμὸν ἑτερόζυγον, = κρουσιμετρέω, Ps.-Phoc.15; “ὡς μήτε κρούσῃς μήθ᾽ ὑπὲρ χεῖλος βάλῃς” S.Fr.796; “κρούων γε μὴν αὐτὰς ἐωνούμην” Eup.184.
9. Med., κρούεσθαι πρύμναν back water, Th.1.51, 54, 3.78; “αἱ πρύμναν κρουόμεναι νῆες” Arr.An.5.17.7 (also in Act., Plb.16.3.8); “κ. ἐπὶ π. τὴν ναῦν” App.BC5.119: hence κρούεσθαι τὸ πτερόν fly backwards, Ael.NA3.13:—also in Act., Plot.2.9.18.