incompréhensible

/ɛ̃.kɔ̃.pʁe.ɑ̃.sibl/
1.
adjectiveSing

impossible to understand

unintelligible (of a text, speech, message, behaviour that can't be made sense of)

Son message est totalement incompréhensible, je ne pige rien.

His message is totally incomprehensible; I don't get it at all.

2.
adjectiveSing

inexplicable

unfathomable (used about actions or reasons that can't be explained)

C'est incompréhensible qu'il ait démissionné sans prévenir.

It's inexplicable that he resigned without warning.