Negative adverb used before verbs, adjectives, and other adverbs to indicate negation; also used as a bound-form prefix to form terms with opposite meanings

(bound form) to feel ashamed; to consider something to be disgraceful

to ask advice or learn from people who are younger, have lower status, or have less experience than oneself; often used in the idiom 不耻下问 bù​chǐ​xià​wèn