There are many signs that involve touching the chin, but they usually have specific meanings and involve different handshapes or movements:
* "Think": The sign for "think" involves touching your index finger to your chin and moving it slightly back and forth.
* "Understand": The sign for "understand" uses a closed fist and taps the chin repeatedly.
* "Question": The sign for "question" involves holding your open hand near your chin and tilting it forward.
If you saw someone using this gesture, it's possible they were:
* Imitating another sign: They might be trying to sign something else but using an incorrect handshape or movement.
* Using a personal sign: Some individuals create their own personal signs, especially within families or close groups.
* Making a gesture: The gesture could be a way to express doubt, thoughtfulness, or uncertainty without a specific meaning in sign language.
If you're interested in learning sign language, it's best to consult reliable resources like a qualified ASL teacher or a reputable sign language dictionary.