1. 降低(自己)的身份;有辱（自己）的人格
If you demean yourself, you do something which makes people have less respect for you.

2. 贬低;贬损
To demean someone or something means to make people have less respect for them.

1. reduce in worth or character, usually verbally

e.g. She tends to put down younger women colleagues
His critics took him down after the lecture

Synonym: take downdegradedisgraceput down