Lexical Definition

‎σπήλαιον‎ spḗlaion (spay'-lah-yon) cave G:N-N
neuter of a presumed derivative of (a grotto)

cave, den.

Abbott-Smith

σπήλαιον, -ου, τό [in LXX chiefly for מְעָרָה ;]
a cave, cavern: Jo 11:38, He 11:38, He 6:15; σ. (EV, den) λῃστῶν (Je 7:11), Mt 21:13, Mk 11:17, Lk 19:46.†

Abbott-Smith References

Book Refs
Jeremiah 7:11
Matthew 21:13
Mark 11:17
Luke 19:46
John 11:38
Hebrews 6:15 · 11:38

Liddell-Scott-Jones

σπήλαιον, τό,

grotto, cavern, [NT+5th c.BC+]; σ. λῃστῶν den of robbers, [LXX+NT]; of a grave, [NT+1st c.AD+]

__2 privy parts, [LXX]
__3 place behind the scenes in a theatre, [Refs 2nd c.AD+]

LSJ Scripture Refs: Rev.6.15LXX.Jer.7.11Matt.21.13John.11.38LXX.Hab.2.15