Role, Part, Duty, Service
noun, suffix
If you have a certain duty then it's your job to play that role. You have to play the part. Like in a play!
やく
The reading is the same as the kanji you learned, meaning you should be able to read this one as well.
役のためにダイエットします。
I'll be on a diet for a role.
ロミオ役はレオナルド・ディカプリオです。
The role of Romeo is Leonardo DiCaprio.
コンビニのアルバイトは、日本社会にとって、あなたが思ってるよりも大切な役です。
Part-time workers at convenience stores play a more important role in Japanese society than you think.