Reference from 1630

Remains of the Early Popular Poetry of England
By William Carew Hazlitt, 1866

Whippit or whippet is used by Taylor, the Water Poet in his Dogge of Warre (Works 1630 ii 232) in the sense of some little breed of dog. Mr. Halliwell (Archaic Dictionary [1847], art. whippit) says:--"A kind of dog in breed between a greyhound and a spaniel." In Udall's Ralph Roister-Doister [1553] some of the characters sing in concert the following song:--

Pipe, mery Annot, &c.
Trilla, trilla, trillarie.
Now Tibbet, now Annot, now Margerie,
Now whippet apace for the maystrie.
But it will not be, our mouth is so drie

Hazlitt combines several sources here. Taylor's reference is from 1630. I can't find a date on Halliwell's listing other than finding that his dictionary was published in 1847. So I don't have a date or further source supporting his comment. Udall may not necessarily been referring to a type of dog.

I've noticed that the quote "A kind of dog in breed between a greyhound and a spaniel" is misquoted in many other later accounts stating "definitively" as a breeding or cross breeding between the two. My interpretation is that the reference by Halliwell did not necessarily indicate a breeding between a greyhound and spaniel, but rather he was providing a size reference or possibly speed in the field. Yes, it's a matter of opinion in a reading of that quote. I know other people who have similar interpretations.