signalyoudaoicibaDictYouDict[signal 词源字典]
signal: [16] Latin signālis meant ‘of a sign’ (it was derived from signum ‘mark, token’, source of English sign). It came to be used as a noun, and passed via medieval Latin signāle into Old French as seignal. This was later relatinized into signal, in which form it was taken over by English. The adjective signal ‘conspicuous’ came from the same ultimate source, but via a more circuitous route. The Italian version of the noun signal is segnale. From it was derived the verb segnalare ‘make famous’, whose past participle segnalato gave French signalé – whence English signal.
=> sign[signal etymology, signal origin, 英语词源]
signal (n.)youdaoicibaDictYouDict
late 14c., "visible sign, indication," from Old French signal, seignal "seal, imprint, sign, mark," from Medieval Latin signale "a signal," from Late Latin signalis (adj.) "used as a signal, pertaining to a sign," from Latin signum "signal, sign" (see sign (n.)). Restricted sense "agreed-upon sign (to commence or desist, etc.) is from 1590s. Meaning "modulation of an electric current" is from 1855.
signal (v.)youdaoicibaDictYouDict
1805, "to make signals to," from signal (n.). Related: Signaled; signaling. Earlier verb was signalize (1650s).
signal (adj.)youdaoicibaDictYouDict
"remarkable, striking, notable" ("serving as a sign"), 1640s, from French signalé, past participle of signaler "to distinguish, signal" (see signal (n.)).