Lexical Definition

‎σύμψυχος‎ sýmpsychos (soom'-psoo-khos) harmonious ^G:A
from ‎σύν‎ and ‎ψυχή‎

like-minded.

• co-spirited, i.e. similar in sentiment

Abbott-Smith

*† σύν-ψυχος (Rec. συμ-), -ον (< ψυχή),
of one mind: Phl 2:2.†

Abbott-Smith References

Liddell-Scott-Jones

σύμψυχος, ον,

__A of one mind, at unity, [NT]; united in soul, τῇ γῇ [Refs 1st c.AD+]

_{LSJ Scripture Refs: Phil.2.2}