Usage: 9 forms in 13 verses
Form Translated As     In Verse(s)
συνέκοψεν cut down LXX.2Kgs.16.17
cut off LXX.2Kgs.18.16
he cut down LXX.Ps.129.4
he cut up LXX.2Kgs.18.4
συνέκοψε he cut off LXX.2Kgs.24.13
συνέκοψαν cut up LXX.2Kgs.25.13
συνέκοψα cut it down LXX.Deut.9.21
συγκόψω I will cut down LXX.Ps.89.23
συγκόψουσι they shall cut down LXX.Isa.2.4
they shall cut me down LXX.Gen.34.30
συγκόψεισ you shall cut LXX.Exod.30.36
συγκόψατε Cut up LXX.Joel.3.10
συγκόπτειν to cut down LXX.2Kgs.10.32

Liddell-Scott-Jones

συγκόπτω (sugkoptō) to cut down G:V

συγκόπτω-τω,

perfect -κέκοφα[Refs 5th c.BC+]:—chop up, [Refs 5th c.BC+]:— passive, to be broken up, [Refs]; συγκεκομμένα μέρη τοῦ σώματος [Refs 1st c.BC+]: metaphorically, πολλαὶ φιλίαι συνεκόπησαν [Refs 2nd c.AD+]

__2 thrash soundly, τινας [Refs 5th c.BC+]; of cocks fighting, variant in [Refs 5th c.BC+]:—passive, συγκεκομμένος [Refs 5th c.BC+]
__3 middle, beat oneself, lament, [Refs 4th c.BC+]
__II cut short a sound or word (see. συγκοπή [Refs 1st c.BC+]:—passive, τὸ -κεκόφθαι [Refs 1st c.BC+]
__III wear out, τὸν μὲν ἀποπνίξας τάχιστα, τοῦ δὲ συγκόψας τὴν δύναμιν [Refs 2nd c.AD+]:—passive, especially in perfect, to be worn out, suffer from συγκοπή (111), [Refs 4th c.BC+]