To deprive of esteem, self-worth, or effectiveness
See syn. study at
The demotion did not abase his credibility with his peers.
You should abase yourselves as miserable friends.
The mother-in-law would demean her, as a way to abase the young wife in the son's eyes.
Don't abase your cousin by making fun of his accent.
Matthew would abase others in an attempt to elevate himself.