signal

n. 信号；暗号；导火线

vt. 标志；用信号通知

adj. 显著的；作为信号的

vi. 发信号

n. (Signal)人名；(瑞典)西格纳尔

中文词源

signal 信号，暗号，标记，表明

sign,标记，记号，-al,名词后缀。引申词义信号，暗号等。

signal: 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 (n.): 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.): 1805, "to make signals to," from signal (n.). Related: Signaled; signaling. Earlier verb was signalize (1650s).
signal (adj.): "remarkable, striking, notable" ("serving as a sign"), 1640s, from French signalé, past participle of signaler "to distinguish, signal" (see signal (n.)).

1、sign- + -al.2、动态的符号，就是信号、暗号。

3. The transmitters will send a signal automatically to a local base station.: 发射台会自动将信号发射到地方基站。

5. Kurdish leaders saw the visit as an important signal of support.: 库尔德领导人将这次访问视作一种表示支持的重要信号。