This is the 3486th most frequent French word.
dennis
The word "dennis" does not have a meaning in French; it is likely a proper noun, such as a name.
Here, 'Dennis' is used as a proper noun referencing a person's name.
Dennis est un coureur talentueux.
Dennis is a talented runner.
In this instance, 'Dennis' is used as a noun referring to a specific brand.
Nous avons acheté une voiture de la marque Dennis.
We bought a car of the Dennis brand.
'Dennis' in this case is again a person's name, showing action and reaction within a narrative.