spill: Spill ‘let fall’ [OE] and spill ‘thin piece of wood’ are distinct words. The former originally meant ‘destroy, kill’; the modern sense ‘allow liquid to pour out or fall’, which did not emerge until the 14th century, arose as a rather grisly metaphor based on the notion of ‘shedding blood’. The ultimate origins of the word, which has relatives in Dutch spillen and Swedish spilla, are not known. Spill ‘thin piece of wood’ was probably borrowed from Middle Low German or Middle Dutch spile ‘splinter, wooden pin, bar, etc’, which also gave English spile ‘bung’ [16].
This in turn went back to a prehistoric West Germanic *spinla (source also of English spindle). The familiar modern use of spill for a ‘small slip of wood, paper, etc used for carrying a flame’ did not emerge until the early 19th century. => spin, spindle
spill (v.)
Old English spillan "destroy, mutilate, kill," also in late Old English "to waste," variant of spildan "destroy," from Proto-Germanic *spilthjan (cognates: Old High German spildan "to spill," Old Saxon spildian "destroy, kill," Old Norse spilla "to destroy," Danish spilde "lose, spill, waste," Middle Dutch spillen "to waste, spend"), from PIE *spel- (1) "to split, break off" (cognates: Middle Dutch spalden, Old High German spaltan "to split;" Greek aspalon "skin, hide," spolas "flayed skin;" Lithuanian spaliai "shives of flax;" Old Church Slavonic rasplatiti "to cleave, split;" Middle Low German spalden, Old High German spaltan "to split;" Sanskrit sphatayati "splits").
Sense of "let (liquid) fall or run out" developed mid-14c. from use of the word in reference to shedding blood (early 14c.). Intransitive sense "to run out and become wasted" is from 1650s. Spill the beans recorded by 1910 in a sense of "spoil the situation;" 1919 as "reveal a secret." To cry for spilt milk (usually with negative) is attested from 1738. Related: Spilled; spilt; spilling.
spill (n.)
1845, originally "a throw or fall from a horse," from spill (v.). Meaning "the spilling of a liquid, amount of spilled stuff" is from 1848.
