This is the 405th most frequent French word.
suisse
Swiss; Switzerland.
Here, 'suisse' is used as an adjective to describe someone's nationality, meaning they are from Switzerland.
Il est suisse et il parle plusieurs langues.
He is Swiss and speaks several languages.
In this sentence, 'suisse' is functioning as an adjective to specify that the flag belongs to Switzerland.
Le drapeau suisse est rouge avec une croix blanche.
The Swiss flag is red with a white cross.
In this sentence, 'Suisse' is a proper noun referring to the country Switzerland.