πταίω (ptaíō|ptah'-yo|verb|to stumble)
[Grk] πταίω LN: 88.291 GK: G4760 Hebrew: יָקֹשׁ‎, נָגַף‎
Derivation: a form of πίπτω;
Strong's: to trip, i.e. (figuratively) to err, sin, fail (of salvation)
KJV: --fall, offend, stumble.
See: πίπτω