This is the 376th most frequent French word.
décidé
Determined; resolute.
'Décidé' is used as a past participle in the passé composé tense to express a completed action taken by the subject.
J'ai décidé de partir tôt ce matin.
I decided to leave early this morning.
In this sentence, 'décidé' is used as an adjective to describe the firmness and determination of the subject.
Il semblait très décidé dans ses actions.
He seemed very determined in his actions.
Here, 'décidée' is used reflexively in pronominal form to indicate that the subject resolved or made a choice to do something.