Usage: 2 forms in 6 verses
Form Translated As     In Verse(s)
πατραδέλφου his uncle LXX.2Sam.23.24
of his uncle LXX.Judg.10.1 • LXX.2Sam.23.9
πατράδελφοσ his uncle LXX.1Sam.10.14
uncle LXX.1Sam.10.15 • LXX.1Chr.27.32

Liddell-Scott-Jones

πατράδελφος (patradelphos) an uncle G:N-M

πατράδελφος-άδελφος [ᾰδ], ὁ,

father's brother, [Refs 4th c.BC+]