Boop

Boop is a slang term used to describe a playful, gentle tap or poke, typically done with the tip of one’s finger. It is often used to convey a sense of affection, playfulness, or to get someone’s attention.

Examples:
1. I saw a cute picture of a puppy on my friend’s phone and couldn’t resist, so I gave it a boop on the nose.
2. Whenever my siblings are engrossed in their video games, I like to sneak up behind them and give them a quick boop on the head to make them jump.