ready and waiting vs waiting

ready and waiting is not a noun while waiting is a noun.

Word	Noun	Adjective	Verb	Adverb
ready and waiting	No	Yes	No	No
waiting	Yes	Yes	No	No

As adjectives, ready and waiting and waiting are synonyms defined as:

ready and waiting and waiting: being and remaining ready and available for use

ready and waiting (noun)	waiting (noun)
	the act of waiting (remaining inactive in one place while expecting something)

ready and waiting (adjective)	waiting (adjective)
being and remaining ready and available for use	being and remaining ready and available for use