Also see definition of "Belly" in Word Study
Study Dictionary
Belly
Belly [EBD]
the seat of the carnal affections (Titus 1:12; Phil. 3:19; Rom. 16:18). The word is used symbolically for the heart (Prov. 18:8; 20:27; 22:18, marg.). The "belly of hell" signifies the grave or underworld (Jonah 2:2).
Belly [NAVE]
BELLY, used figuratively for the seat of the affections, Job 15:2, 35; 20:20; Psa. 44:25; Prov. 18:20; 20:27, 30; Hab. 3:16; John 7:38; Tit. 1:12.BELLY [ISBE]
BELLY - bel'-i: gachon = "the external abdomen" (Gen 3:14; Lev 11:42). qobhah = "the abdominal cavity" (Nu 25:8 the American Standard Revised Version "body"). beTen = "the internal abdomen," "the womb" (1 Ki 7:20; Job 15:2,35 the King James Version; Job 20:15,23; 40:16; Ps 17,14; Prov 13:25; 18:20; Jer 1:5; Ezek 3:3); also figuratively "the internal regions," "the body of anything" (Jon 2:2). me`eh = "intestines," "abdomen" (Dan 2:32; Jon 1:17; 2:1,2). In the New Testament koilia = "a cavity," espec ially the abdominal (Mt 12:40; 15:17; Mk 7:19); the seat of appetite and of the carnal affections (Rom 16:18; 1 Cor 6:13; Phil 3:19; Rev 10:9,10); the innermost of the soul (the American Revised Version, margin Jn 7:38).Frank E. Hirsch
Also see definition of "Belly" in Word Study