Thanks for your question. Some of the older monks and nuns in our communities would know the Trappist sign language taught to them in the 1940’s and 1950’s when they entered monastic life. Today, you might see these older members of the community making signs to one another out of force of habit.
There were signs used so often as to be performed almost unconsciously: a rap on the breast with a closed fist: “pardon me.” The two index fingers joined in the shape of a triangle: “finished”. The thumb propped under the chin, which is the sign for “death”, but can mean: “wrap it up.” or “that’s enough”.
On a happier note – the fingers splayed and passed over the face like a fan: “beautiful”. (I once saw a monk in his eighties actually sign the 1941 Betty Grable movie: “Moon over Miami”!)
In 1969 Trappist monks and nuns began to rethink the essential monastic value of community and how best to live that. Rather than strict silence, requiring an elaborate sign language, (by which people were communicating after all!), we instituted places and times for silence. In the process we discovered that silence is actually better observed and deeper when provision is made for the essential human need for communication at certain times. Consequently, newcomers to monastic life after about 1980 would not have been taught any but a few of the old Trappist signs.