to establish the recommended safe speed of (an airplane)
to draw a canceling red line through (an item on a list)
to engage in redlining
one that redlines (to withhold loans or insurance from certain neighborhoods) [n REDLINERS]
a. the maximum rotational speed, or angular velocity, of the engine crankshaft that is considered safe: often measured in rpm b. red line or boundary of a red area that delineates such a value, as on a tachometer