pastie
/pay'stee/ An adhesive label designed to be attached to a key
on a keyboard to indicate some non-standard character which
can be accessed through that key. Pasties are likely to be
used in APL environments, where almost every key is associated
with a special character. A pastie on the R key, for example,
might remind the user that it is used to generate the rho
character. The term properly refers to nipple-concealing
devices formerly worn by strippers in concession to
indecent-exposure laws; compare {tits on a keyboard}.
[{Jargon File}]