1. cosine; the trigonometric function that gives the ratio of the adjacent side to the hypotenuse in a right triangle
Usage: mathematics; abbreviation
2. a type of lettuce with long, crisp leaves
Usage: also called romaine lettuce

1. because
Usage: informal; chiefly British

Examples

• Calculate the cos of 60 degrees.
• The cos function is essential in trigonometry.
• We need cos lettuce for the Caesar salad.
• Cos has a crisp texture and slightly bitter taste.
• I can’t come cos I’m busy tonight.
• She left early cos she wasn’t feeling well.