How do you say corrupt in Japanese?

Corrupt has several meanings in English, and therefore there are a couple of Words in Japanese for each case:

Corrupt - As in destroy integrity

堕落する (daraku suru) means "to corrupt", and 堕落 (daraku) is "corrupt". As an adjective, you can also use 邪悪な (jaaku na) which is "wicked/evil".

Corrupt - As in dishonest

買収された (baishuusareta) is an an adjective for a person that is already acting with such dishonest practices. 買収する (baishuusuru) is itself a verb for "to bribe".