G5421
φρέαρ
well/abyss
φρέαρ, -ατος, τό [in LXX chiefly for בְּאֵר ;] a well: Luk.14:5, Sng.4:11-12; φ. τῆς ἀβύσσου, Rev.9:1-2.† (AS)
The KJV translates G5421 in the following manner:
pit (10x), well (4x)
Full Thayer's lexicon entry
φρέαρ — phréar
φρέαρ, φρεαρατος, τό, from the Homer hymn Cer. 99 and Herodotus 6, 119 down; the Sept. for בְּאֵר and (in 1Sa 19:22; 2Sa 3:26; Jer 48:7; Jer 48:9 בּור (a pit, cistern), a well: Luk 14:5; Joh 4:11 f; φρέαρ τῆς ἀβύσσου, the pit of the abyss (because the nether world is thought to increase in size the further it extends from the surface of the earth and so to resemble a cistern, the orifice of which is narrow), Rev 9:1 f.
5 occurrences
Luke (1), John (2), Revelation of John (2)