Lexical Definition

‎πορθέω‎ porthéō (por-theh'-o) to lay waste G:V
prolongation from (to sack)

destroy, waste.

Usage: 3 forms in 3 verses
Form Translated As     In Verse(s)
ἐπόρθουν was destroying Gal.1.13
ἐπόρθει he was destroying Gal.1.23
πορθήσασ having caused havoc Acts.9.21

Abbott-Smith

** πορθέω collat. form (in cl. chiefly poët.) of πέρθω, [in LXX: IV Mac 4:23 11:4*;]
to destroy, ravage: Ac 9:21, Ga 1:13, 23.†

Abbott-Smith References

Book Refs
Acts 9:21
Galatians 1:13 · 1:23

Liddell-Scott-Jones

πορθέω-έω,

collateral form of πέρθω (more used in Prose), destroy, ravage, plunder, πόλεας καὶ τείχεα [πορθέωῆσαι 1st c.BC: Diodorus Siculus Historicus 12.34; π. ἐκ τῶν ἱερῶν τὰ ἀγάλματα 2nd c.AD: Athenaeus Epigrammaticus 12.523b ">Refs 8th c.BC+]:—passive, πᾶν τὸ ἄστυ ἐπορθέωέετο [πορθέωημένης 5th-6th c.BC: Isocrates Orator 10.49; τἀργύρια πορθέωεῖται ">Refs 5th c.BC+]is carried off, [Refs 5th c.BC+]

__2 in present and imperfect, sometimes endeavour to destroy, besiege a town, [Refs 5th c.BC+]
__3 of persons, destroy, ruin, θεοὺς τοὺς ἐγγενεῖς [Refs 5th c.BC+]: absolutely, do havoc, [Refs]: especially in passive, αὐτοὶ ὑφ᾽ αὑτῶν.. πορθέωούμεθα. [πορθέωούμεθα [prev. author] “Ch.” 691 ">Refs 4th c.BC+]; of women, κόραι βία πρὸς ἀνδρῶν πορθέωούμεναι [Refs 5th c.BC+]; σκόροδα πορθέωούμενος robbed of them, Comedy texts phrase in [Refs 5th c.BC+]