αφορμή

Etymology
From, from /  +.

Noun

 * 1) pretext, cause, reason, motive, excuse, occasion surface/trigger event or circumstance
 * 2) grudge, complaint long-term animosity or ill will about something or someone
 * 1) grudge, complaint long-term animosity or ill will about something or someone
 * 1) grudge, complaint long-term animosity or ill will about something or someone
 * 1) grudge, complaint long-term animosity or ill will about something or someone

Usage notes
Usually implies surface cause or reason used to mask the true motivation, which is expressed by.