tropic vs tropics

tropic and tropics both are nouns.

Word	Noun	Adjective	Verb	Adverb
tropic	Yes	Yes	No	No
tropics	Yes	No	No	No

tropic (noun)	tropics (noun)
either of two parallels of latitude about 23.5 degrees to the north and south of the equator representing the points farthest north and south at which the sun can shine directly overhead and constituting the boundaries of the Torrid Zone or tropics	the part of the Earth's surface between the Tropic of Cancer and the Tropic of Capricorn; characterized by a hot climate

tropic (adjective)	tropics (adjective)
relating to or situated in or characteristic of the tropics (the region on either side of the equator)
of weather or climate; hot and humid as in the tropics