handwave
verbUK /ˈhænd.weɪv/
US /ˈhænd.weɪv/
To wave your hand in the air to say hello or goodbye.
She gave a quick handwave to her friend across the street.
OTHER MEANINGS
2. To explain something in a vague way without real proof.
He handwaved the problem instead of giving a clear answer.
3. To dismiss or brush off a question with a quick motion or vague words.
The teacher handwaved my question and moved on.
4. A quick, casual wave of the hand.
With a friendly handwave, he left the room.