BDAG lists πιέζω (to press, put pressure on) and πιάζω (to grasp, seize, catch) as separate words. LSJ has
πιάζω , Dor. and later Att. for πιέζω (q. v.).
Are these words separate or not?
πιάζω 1 aor. ἐπίασα. Pass.: fut. πιασθήσεται Sir 23:1; aor. ἐπιάσθην (Alcman 28 D.2; Theocr. 4, 35; Sethianische Verfluchungstafeln 49, 58; 59 Wünsch [1898]; POxy 812, 5 [5 B.C.]; PHamb 6, 16; LXX [s. Thackeray 282.—B-D-F §29, 2; 101 p. 48; Mlt-H. 69; 254; 405]; TestNapht 5:2, 3) Doric and colloq. for Attic πιέζω (s. Thumb 67 note) in our lit. only in the foll. senses
① to take firm hold of, grasp neutral take (hold of) τινά τῆς χειρός someone by the hand Ac 3:7 (cp. Theocr. 4, 35 τὸν ταῦρον ὁπλᾶς).
② to seize with intent to overpower or gain control
ⓐ of humans seize, arrest, take into custody (cp. BGU 325, 2 λῃστοπιαστής) τινά someone (PGM 5, 172 κλέπτην) J 7:30, 32, 44; 8:20; 10:39; 11:57; PEg2, 26 and 28; 2 Cor 11:32. ὸ̔ν πιάσας ἔθετο εἰς φυλακήν Ac 12:4.
ⓑ of animals catch (SSol 2:15) of fish (PLond II, 483, 76 p. 328 [616 A.D.]) J 21:3, 10. Pass. ἐπιάσθη τὸ θηρίον Rv 19:20. On πιάζω and corresponding form πιέζω, s. GShipp, Modern Greek Evidence for the Ancient Greek Vocabulary ’79, 454f.—B. 575; 744. New Docs 3, 82.—DELG s.v. πιέζω. M-M.
πίε, πιεῖν, πίεσαι s. πίνω.
πιέζω pass.: pf. ptc. πεπιεσμένος; 3 sg. aor. ἐπιέσθη Papias (v.l.) (Hom.+; Hero Alex. I p. 58, 4; SIG 904, 7; PCairZen 378, 11 [III B.C.]; PBerlZill 1, 41; Mi 6:15 πιέσεις ἐλαίαν; TestSol 1:2 C; Philo, Migr. Abr. 157, Aet. M. 129; Jos., Ant. 17, 28. See πιάζω) press μέτρον πεπιεσμένον a measure that is pressed down Lk 6:38. ὑπὸ τῆς ἁμάξης … ἐπιέσθη ὥστε τὰ ἔγκατα αὐτοῦ ἐκκενωθήναι Judas was so pinned by the wagon that his entrails came out Papias (3:2 v.l. [Preuschen p. 98 app. for ln. 8]).—S. Shipp, πιάζω, end. B. 575; 744. New Docs 3, 82.—DELG. M-M.
Arndt, W., Danker, F. W., & Bauer, W. (2000). A Greek-English lexicon of the New Testament and other early Christian literature (3rd ed.) (812). Chicago: University of Chicago Press.