This is the 1600th most frequent Japanese word.
強制
Compulsion; coercion; enforcement.
Here, "強制的に" (kyouseiteki ni) is used as an adverb to describe the enforced nature of the action.
彼は強制的に部屋を掃除させられた。
He was forced to clean the room.
In this sentence, "強制" (kyousei) is a noun representing the concept of enforcement or coercion.
強制は時に必要になることもある。
Sometimes, enforcement may become necessary.
"強制される" (kyousei sareru) is a passive verb form, meaning "to be enforced."