input vs input signal

input and input signal both are nouns.

Word	Noun	Adjective	Verb	Adverb
input	Yes	No	Yes	No
input signal	Yes	No	No	No

As nouns, input and input signal are synonyms defined as:

input (noun)	input signal (noun)
a component of production; something that goes into the production of output	signal going into an electronic system
any stimulating information or event; acts to arouse action
signal going into an electronic system
a statement that expresses a personal opinion or belief or adds information

input (verb)	input signal (verb)
enter (data or a program) into a computer