Douglas Harper's Etymology Dictionary
self-deprecation
1843, from self- + deprecation.
Wiktionary
self-deprecation
n. The disparagement of one's own abilities
Wikipedia
Self-deprecation
Self-deprecation is the act of reprimanding oneself by belittling, undervaluing, or disparaging oneself, or being excessively modest. It can be used in humor and tension release.
Usage examples of "self-deprecation".
To erase that self-deprecation, to make amends for his own maladroitness, F'nor leaned across the table to kiss her on the lips.