presignal adjective 1noun 1forms 1 adjective1 •Before a signal.Another experiment showed that presignal information about which of two frequencies was to be presented aids detection considerably, but such information does not entirely eliminate the decrement. — 1959 noun1 •A signal that occurs before some occurrence, as a warning or to trigger an automatic preparation.In this case, a presignal from the ATS could be interfaced with the elevator controls for that purpose. — 2011 formspresignals
