E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
(Latin nodus, French nud, Danish knude, Dutch knot, Anglo-Saxon cnotta, allied to knit.)
He has tied a knot with hs tongue he cannot untie with his teeth. He has got married. He has tied the marriage knot by saying, I take thee for my wedded wife, etc., but the knot is not to be untied so easily.
The Gordian knot. (See GORDIAN.)
The marriage knot. (See MARRIAGE.)
The ship went six or seven knots an hour. Miles. The log-line is divided into lengths by knots, each length is the same proportion of a nautical mile as half a minute is of an hour. The logline being cast over, note is taken of the number of knots run out in half a minute, and this number shows the rate per hour.
The length of a knot is 47:33 feet when used with a 28-second glass, but 50:75 feet when the glass runs 30 seconds.
True lovers knot. Sir Thomas Browne thinks the knot owes its origin to the nodus Herculanus, a snaky complication in the caduceus or rod of Mercury, in which form the woollen girdle of the Greek brides was fastened.
To seek for a knot in a rush. Seeking for something that does not exist. Not a very wise phrase, seeing there are jointed rushes, probably not known when the proverb was first current. The Juncus acutiflorus, the Juncus lampocarpus, the Juncus obtusiflorus, and the Juncus polycephalus, are all jointed rushes.