Wiktionary
at a rate of knots
prep.phr. quickly; rapidly; fast.
Usage examples of "at a rate of knots".
A crashing sound like that made by a herd of hippopotami going through the reeds on a river bank attracted my notice and I beheld Spode approaching at a rate of knots with the obvious intention of resuming at as early a date as possible his investigations into the colour of Gussie's insides which Stinker's intervention had compelled him to file under the head of unfinished business.
I looked down to watch Daniel crawling towards me at a rate of knots.