GENERAL INFO

Compris is the past participle of the verb comprendre (to understand).

It means “understood.”

USAGE

It is used with the auxiliary avoir to form compound tenses:

"J’ai compris." (I understood / I have understood)

"Tu as compris la leçon." (You understood the lesson)

It can also be used in expressions:

"C’est compris." (It’s understood)

TRAPS

No preposition is used before the object:

"j’ai compris la leçon" ; NOT "j'ai compris de la leçon"

As a past participle with avoir, it usually does not agree, unless the direct object comes before:

"Les leçons que j’ai comprises" (The lessons that I understood)

Also note the irregular pattern similar to prendre.