Lexical Definition

‎ἐπισυναγωγή‎ episynagōgḗ (ep-ee-soon-ag-o-gay') gathering G:N-F
from ‎ἐπισυνάγω‎

assembling (gathering) together.

Usage: 2 forms in 2 verses
Form Translated As     In Verse(s)
ἐπισυναγωγῆσ gathering together 2Thess.2.1
ἐπισυναγωγὴν assembling together Heb.10.25

Abbott-Smith

**† ἐπι-συν-αγωγή, -ῆς, ἡ (< ἐπισυνάγω), [in LXX: II Mac 2:7 * ;]
a gathering together, assembly: He 10:25; seq. ἐπί, II Th 2:1 (cf. II Mac, l.c.).†

Abbott-Smith References

Book Refs
2 Thessalonians 2:1
Hebrews 10:25

Liddell-Scott-Jones

ἐπισυναγωγή-ᾰγωγή, ,

gathering or being gathered together, [LXX+NT]

__b collection of a sum of money, [Refs 2nd c.BC+]
__2 collective view, table, ὁρίων [Refs 2nd c.AD+]
__3 plural, successive additions, [Refs]
__4 Astrology texts, aggregation of planets in contact, [Refs 3rd c.AD+]

LSJ Scripture Refs: 2Thess.2.1