also knothole, "hole left in a plank or board after a knot has dropped out," 1726, see knot (n.) + hole (n.).
Entries linking to knot-hole
knot n.
Old English cnotta "intertwining of ropes, cords, etc.," from Proto-Germanic *knuttan- (source also of Low German knütte, Old Frisian knotta "knot," Dutch knot, Old High German knoto, German Knoten, perhaps also Old Norse knutr "knot, knob"). For pronunciation, see kn-.
Figurative sense of "difficult problem, a perplexity" was in Old English (compare Gordian knot). Symbolic of the bond of wedlock from early 13c. As an ornament of dress, first attested c. 1400. Meaning "thickened part or protuberance on tissue of a plant" is from late 14c. As "small group or cluster of persons" late 14c.
The nautical unit of measure of speed (1630s) is from the practice of attaching knotted string to the log line at equal distances (see log (n.2)). The ship's speed can be measured by the number of knots that play out while the sand glass is running.
The distance between the knots on the log-line should contain 1/120 of a mile, supposing the glass to run exactly half a minute. [Jorge Juan and Antonio de Ulloa, "A Voyage to South America" 1760]
Hence the word knot came also to be used as the equivalent of a nautical mile (in pre-World War II use in U.S. and Britain, about 6,080 feet). A speed of 10 knots will cover ten nautical miles in an hour (equivalent to a land speed of about 11.5 mph).
hole n.
Old English hol (adj.) "hollow, concave;" as a noun, "hollow place; cave; orifice; perforation," from Proto-Germanic *hulan (source also of Old Saxon, Old Frisian, Old High German hol, Middle Dutch hool, Old Norse holr, German hohl "hollow," Gothic us-hulon "to hollow out"), from PIE root *kel- (1) "to cover, conceal, save." As an adjective, it has been displaced by hollow, which in Old English was only a noun, meaning "excavated habitation of certain wild animals."
As a contemptuous word for "small dingy lodging or abode" it is attested from 1610s. Meaning "a fix, scrape, mess" is from 1760. Obscene slang use for "vulva" is implied from mid-14c. Golfing hole-in-one is from 1914; as a verbal phrase from 1913. To need (something) like a hole in the head, applied to something useless or detrimental, first recorded 1944 in entertainment publications, probably a translation of a Yiddish expression such as ich darf es vi a loch in kop.