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.

[EX Q]: cerebral œdema (or cerebral edema) is a build-up of extra fluid in the brain.
[EX A]: cerebral edema

[EX Q]: dominoes is a game played with small tiles called dominoes.
[EX A]: dominoes

[EX Q]: the anglican communion is an association of all anglican churches in full communion with the church of england.
[EX A]:
anglican communion