leg vs pair of trousers

leg and pair of trousers both are nouns.

Word	Noun	Adjective	Verb	Adverb
leg	Yes	No	No	No
pair of trousers	Yes	No	No	No

leg (noun)	pair of trousers (noun)
a section or portion of a journey or course	(usually in the plural) a garment extending from the waist to the knee or ankle, covering each leg separately
(nautical) the distance traveled by a sailing vessel on a single tack
a cloth covering consisting of the part of a pair of trousers that covers a person's leg
one of the supports for a piece of furniture
a prosthesis that replaces a missing leg
a human limb; commonly used to refer to a whole limb but technically only the part of the limb between the knee and ankle
a structure in animals that is similar to a human leg and used for locomotion
the limb of an animal used for food
a part of a forked or branching shape