Strong's #172: akakos (pronounced ak'-ak-os)

from 1 (as a negative particle) and 2556; not bad, i.e. (objectively) innocent or (subjectively) unsuspecting:--harmless, simple.

Thayer's Greek Lexicon:

̓́

akakos

1) without guile or fraud, harmless, free from guilt

2) fearing no evil from others, distrusting no one

Part of Speech: adjective

Relation: from G1 (as a negative particle) and G2556

Citing in TDNT: 3:482, 391

Usage:

This word is used 2 times:

 

Romans 16:18: "the hearts of the simple."
Hebrews 7:26: "became us, who is holy, harmless, undefiled, separate from sinners,"