This is the 7339th most frequent French word.
ocean
A vast expanse of saltwater covering large portions of the Earth's surface.
Here, 'océan' is used as a noun to refer to a specific body of water, the Atlantic Ocean.
L'océan Atlantique est immense et surprenant.
The Atlantic Ocean is vast and awe-inspiring.
In this sentence, 'océan' is used to generally denote any large body of seawater suitable for swimming or recreational activities.
J'adore nager dans l'océan pendant l'été.
I love swimming in the ocean during the summer.
Here, 'océans' is pluralized to speak about oceans collectively, discussing a global environmental issue.