TASK DEFINITION: Generate a topic word for the given sentence. A topic word is usually the name of a person, place, animal, concept or object the sentence is focusing on.
PROBLEM: the kiwi is a bird from new zealand.

SOLUTION: kiwi

PROBLEM: varicose veins are a condition in which the veins in the leg area have become enlarged.

SOLUTION: varicose veins

PROBLEM: the timber rattlesnake ("crotalus horridus") is a species of venomous pit vipers.

SOLUTION:
timber rattlesnake