This is the 6467th most frequent Japanese word.
スーツ
Suit.
Here, 'スーツ' refers to a set of formal clothing, typically consisting of a jacket and trousers, suitable for business or formal occasions.
彼は新しいスーツを買いました。
He bought a new suit.
In this context, 'スーツ' implies the recommendation to wear formal clothing for an appropriate occasion.
今日はスーツを着たほうがいいですよ。
You should wear a suit today.
Here, 'スーツ' is part of 'スーツケース', meaning 'suitcase', which is a large case used for travel and carrying belongings.