Language that is
articulated through
movements of the
hands and
arms,
and
facial mimicry, as opposed to the
vocal organs. Such languages appear almost
exclusively among
communites of
deaf people, but sign languages
of various degrees of
complexity are also used in other communities where
speaking is
impossible or
impractical, such as in certain
monasteries
and
nunneries.
Contrary to popular belief, there isn't any one sign language -- sign
languages are as diverse in grammar and vocabulary as spoken languages
are. There have been some attempts to make an artificial sign
language suitable for international communication (see Gestuno) but so far with little
success.
It is often the case that the borders of spoken languages don't overlap
with the borders of sign languages. For instance, the US and the UK
both have English as their primary, spoken language, but deaf
communities in the two countries use sign languages that are mutually
unintelligible (Ameslan/ASL and BSL, respectively).
Templeton: the gestures of hearing people is not a
language; they are
paralinguistic. Although some of the
lexemes in sign languages are borrowed from
gestures and
pantomime, most of them soon become
opaque, that is, hearing people (or deaf people with another
sign language) can't guess its meaning correctly. When they are told what the sign means, and asked to take a
guess at its
origin, they rarely guess correctly.