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: hair straightening is when a person makes their hair straighter.

SOLUTION: hair straightening

PROBLEM: the boeing international headquarters (colloquially known as the boeing building and formerly known as the morton international building) is a 36-floor skyscraper located in the near west side of chicago.

SOLUTION: boeing international headquarters

PROBLEM: khanda is a symbol of sikhism.

SOLUTION:
khanda