[sig.nal] n [ME, fr. MF, fr. ML signale, fr. LL, neut. of signalis of a sign, fr. L signum] (14c) 1: sign, indication
2. a: an act, event, or watchword that has been agreed on as the occasion of concerted action b: something that incites to action
3: something (as a sound, gesture, or object) that conveys notice or warning
4. a: an object used to transmit or convey information beyond the range of human voice b: the sound or image conveyed in telegraphy, telephony, radio, radar, or television c: a detectable physical quantity or impulse (as a voltage, current, or magnetic field strength) by which messages or information can be transmitted
[2]signal vb sig.naled or sig.nalled ; sig.nal.ing or sig.nal.ling vt (1805) 1: to notify by a signal "~ the fleet to turn back"
2. a: to communicate or indicate by or as if by signals "~ed the end of an era" b: to constitute a characteristic feature of (a meaningful linguistic form) ~ vi: to make or send a signal -- sig.nal.er or sig.nal.ler n [3]signal adj [modif. of F signale, pp. of signaler to distinguish, fr. OIt segnalare to signal, distinguish, fr. segnale signal, fr. ML signale] (1641): distinguished from the ordinary "~ achievement"