This is the 999th most frequent French word.
basée
Based.
Here, 'basée' is the past participle of 'baser,' used as a predicate adjective agreeing in gender and number with 'La décision', describing it as something grounded or founded upon solid facts.
La décision est basée sur des faits solides.
The decision is based on solid facts.
In this sentence, 'basée' serves as an attribute to modify 'Une théorie,' demonstrating a state of being founded upon given hypotheses.
Une théorie basée sur des hypothèses peut évoluer.
A theory based on hypotheses can evolve.
The word 'basée' here acts as a modifier to 'Cette histoire,' implying that the story derives its basis or inspiration from actual events.