〜がてら

Meaning

Indicates doing another action while at it, on the occasion of one action. A colloquial expression for getting something else done along with one's main purpose.

Examples

散歩がてら、近所の本屋に立ち寄った。 I stopped by a nearby bookstore while taking a walk.
駅まで見送りがてら、少し話をしよう。 Let us talk a bit while I walk you to the station.
買い物がてら、図書館で本を返してきた。 While doing some shopping, I also returned books to the library.