How to describe gesture to shut up?

I want to use a word/phrase/idiom etc. to describe someone action by which they try to stop another person talk or sharing their plans.

I want specifically to use it in following situation:

During conversation with my uncle, he was telling me their future plans to sell house but my Aunt stopped him by secretly putting her finger on lips as a gesture to shut up.

Solution 1:

It is generally called shush gesture. See this Wikipedia link.

Solution 2:

Shush usually means to make a "shhhh!" sound, and can be accompanied by a finger to the lips.

If your text doesn't absolutely have to mention the finger gesture explicitly, shush as a verb fits well here, especially with secret:

During conversation with my uncle, he was telling me their future plans to sell house but my Aunt secretly shushed him.

Solution 3:

I don't know a name for the gesture (Shyam's answer of "shush gesture" doesn't recall this to me - it rather makes me think of somebody sticking a hand out palm-downwards and waving it downwards repeatedly).

The phrase I know to describe it is "putting a finger to one's lips". I notice that if you do not know the gesture, this is not enough information to describe it, but that is the phrase I am familiar with.

Many (most?) common gestures do not have a particular name, precisely because they are gestures, not part of spoken language. The list of gestures in the Wikipedia article listed often have what appear to me to be names applied simply for the purpose of being able to write about them. Google ngrams shows no results for "shush gesture", but some for "finger to the lips".

Solution 4:

What you've said may be as good as a description as there is, otherwise, the gesture could be interpreted in more than one way. Colin mentions pumping an open palm down toward the ground, as if one is dribbling an imaginary basketball, which I'd usually interpret as "Keep it down!" or "Turn down the volume!" but could also mean "Be quiet!" in small room. Yet another gesture is to put one's hand horizontally across the throat, palm down, and then pull it in the direction of elbow with a sharp yanking motion. This is often translated as "Cut!" but is often used as a sign to mean "Cut! Quiet! Shut up! Stop talking now!" when someone is about to spill the beans, like your uncle was about to do.

The first term that came to my mind was shh sign, but that won't be any less subject to interpretation than hush sign, shush sign, or be-quiet sign.

I've seen the gesture you descibed used in an attempt to halt a conversation, or to exhort the participants to speak more quietly, but not necessarily shut up.

All that said, instead of scrounging for a universally-recognized name, I might opt for some more vivid language that gets the message across unambiguously – something like:

During conversation with my uncle, he was telling me their future plans to sell house when my Aunt stopped him by hastily putting her index finger to her lips and gazing at him with the intense glare of an angry librarian.

Solution 5:

Another gesture would be quickly drawing one's thumb & forefinger across one's lips, meaning "zip it up."

When I glimpsed my aunt's fingers zip across her mouth, I knew she was signaling my uncle to stop talking about selling the house.

Another gesture, seen in recording studios, for example, is the forefinger drawn quickly across the throat, meaning "cut" or "stop talking."