bowels, inward affection, + tender mercy

Boyd’s Bible Dictionary:

Used figuratively for the emotions (Col. 3:12; 1 John 3:17).

Concise Bible Dictionary:

Used symbolically for deep tenderness, pity and compassion (Gen. 43:30; 1 Kings 3:26; Phil. 1:8; Phil. 2:1).

Strong’s Dictionary of Greek Words:

Number:
4698 (find all occurrences in KJV Bible)
Greek:
σπλάγχνον
Transliteration:
splagchnon
Phonic:
splangkh’-non
Meaning:
probably strengthened from σπλήν (the "spleen"); an intestine (plural); figuratively, pity or sympathy
KJV Usage:
bowels, inward affection, + tender mercy