A type of lettuce with crisp, narrow leaves that form a tall head; also known as Romaine lettuce. noun
She added chopped cos to the salad for extra crunch.
Cos lettuce is often used in Caesar salads due to its sturdy leaves.
An abbreviation for cosine, a trigonometric function that represents the ratio of the adjacent side to the hypotenuse of a right-angled triangle. noun
In trigonometry, cos 30° is equal to √3/2.
The student calculated the value of cos θ using a calculator.
An informal or dialectal contraction of 'because', used in casual speech or writing. conjunction
I'm not going to the party cos I'm feeling tired.
She didn't finish her homework cos she was too busy.