Lexical Definition

‎גָּדַף‎ gâdaph (gaw-daf') to blaspheme H:V
a primitive root

blaspheme, reproach.

1) to revile men, blaspheme God
1a) (Piel)
1a1) to revile (between men)
1a2) to blaspheme (God)

See Greek: βλασφημέω · καταλαλέω · παροργίζω

Usage: 5 forms in 7 verses
Form Translated As     In Verse(s)
מְגַדֵּ֑ף blaspheming Num.15.30
וּמְגַדֵּ֑ף and reviles Ps.44.16
וְגִדַּ֔פְתָּ and have you blasphemed 2Kgs.19.22Isa.37.23
גִּדְּפ֤וּ they blasphemed Ezek.20.27
גִּדְּפ֛וּ they have blasphemed 2Kgs.19.6Isa.37.6

Brown-Driver-Briggs

[‎גָּדַף‎] verb only Pi`el revile, blaspheme (Late Hebrew ‎גָּדַף‎ cut, wound, then (especially Pi) revile; Arabic cut, cut off, II. deny a favour, be ungrateful, etc.; Aramaic Pa`el ‎גַּדֵּף‎, , revile) — Perfect 2 masculine singular ‎וְגִדַּפְתָּ‎ 2Kgs 19:22 = Isa 37:23 3 plural ‎גִּדְּפוּ‎ 2Kgs 19:6 = Isa 37:6 Participle ‎מְגַדֵּף‎ Num 15:30; Ps 44:17*

1. revile, between man and man, (absolute) ‎קוֺל‎ ‎מְחָרֵף וּמְגַדֵּף‎ Ps 44:17* the voice of (him that) reproacheth and revileth.

2. blaspheme, followed by accusative ‎׳‎‎י‎ Num 15:30 (P); 2Kgs 19:22 = Isa 37:23 (|| ‎חֵרֵף‎; object ‎אֶתמִֿי‎, reference to ‎׳‎‎י‎ as above); Ezek 20:27 2 accusative ‎הַדְּבָרִים‎ ‎נַעֲרֵי מֶלֶךְ אַשּׁוּר אֹתִי‎ ‎׳‎‎אֲשֶׁר ג‎ ... 2Kgs 19:6 = Isa 37:6 the words with which the servants of the king of Assyria blaspheme me.

Brown-Driver-Briggs References

Book Refs
Numbers 15:30
2 Kings 19:6 · 19:22
Psalms 44:17*
Isaiah 37:6 · 37:23
Ezekiel 20:27