also: ボランテア · ボランテァ
noun
Refers to a person who does unpaid work for a cause or organization, or the activity itself. Common in contexts like volunteer activities, volunteer work, and volunteer groups.
週末にボランティアで公園の掃除をした。
I did volunteer work cleaning the park on the weekend.
彼女は被災地でボランティア
She is working as a volunteer in the disaster area.