undermine
verb/miˈnaɾ/medium
mi·nar
Definition
To dig mines or underground tunnels. Figuratively, to weaken gradually; to sabotage.
The soldiers tried to undermine the enemy's defenses.
Constant criticism began to undermine his self-confidence.
Common collocations
undermine confidenceundermine moraleundermine the foundationsundermine authority
Etymology
Do francês 'miner'.