Lexical Definition

‎καταλλαγή‎ katallagḗ (kat-al-lag-ay') reconciliation G:N-F
from ‎καταλλάσσω‎

atonement, reconciliation(-ing).

Usage: 4 forms in 5 verses
Form Translated As     In Verse(s)
καταλλαγῆσ of reconciliation 2Cor.5.182Cor.5.19
καταλλαγὴν reconciliation Rom.5.11
καταλλαγὴ reconciliation Rom.11.15
καταλλαγήσ reparation LXX.Isa.9.5

Abbott-Smith

κατ-αλλαγή, -ῆς, ἡ (< καταλλάσσω), [in LXX: Is 9:5*(4*), II Mac 5:20*;]
1. exchange.
2. reconciliation: Ro 5:11; κ. κόσμου, Ro 11:15; διακονία τῆς κ., II Co 5:18; λόγος τῆς κ., II Co 5:19.†

Abbott-Smith References

Book Refs
Isaiah 9:4* · 9:5*
Romans 5:11 · 11:15
2 Corinthians 5:18 · 5:19

Liddell-Scott-Jones

καταλλαγή-ᾰγή, ,

exchange, especially of money, [Refs 4th c.BC+]

__2 money-changer's profit, agio, [Refs 4th c.BC+]
__3 freight, merchandise, metaphorically, [ἀραὶ] βαρεῖαι κ.[Refs 4th c.BC+]
__4 change, difference, [Refs 1st c.BC+]
__II change from enmity to friendship, reconciliation, καταλλαγήαγὰς ποιεῖσθαι πρός τινας [Refs 5th c.BC+]
__II.2 reconciliation of sinners with God, [NT]

LSJ Scripture Refs: 2Cor.5.18Rom.11.15