collar tug
When the collar of any piece of clothing is pulled down or out, often to indicate that a character is feeling hot and is getting fresh air into their clothes or as a sign of nervousness.
Not to be confused with shirt pull or any other form of clothes pull, which is used for when a character intentionally pulls down on the collar of a shirt/dress/etc. to reveal the cleavage, breasts or pectorals, although sometimes it may come as a result of a collar tug, in which case it should be tagged as both, and even as accidental exposure if it applies.
Also, not to be confused with shirt tug, which is used for when a character pulls down on the bottom of the shirt.
Also also, not to be confused with collar grab.