blood

blood in medieval science and medicine, blood was regarded as one of the four bodily humours, believed to be associated with a confident and optimistic, or sanguine, temperament.

Blood is traditionally used to denote the killing of a person, or guilt for a death, as in blood on one's hands.


blood and iron military force as distinguished from diplomacy; the phrase is a translation of German Blut und Eisen, and is particularly associated with the German statesman Otto von Bismarck (1815–98).
blood-and-thunder a story which features bloodshed and violence; the term is recorded from the mid 19th century.
blood is thicker than water in the end a family connection will outweigh other relationships. Recorded from the early 19th century, but a related 12th-century saying in German runs, ‘I hear it said that kin-blood is not spoiled by water’, and Lydgate in the Troy Book (1412) has, ‘For naturely blod will ay of kynde Draw vn-to blod, wher he may it fynde.’
the blood of the martyrs is the seed of the Church the Church thrives on persecution. Recorded in English as a saying from the mid 16th century; the 3rd century early Christian writer Tertullian has, ‘As often as we are mown down by you, the more we grow in numbers; the blood of Christians is the seed.’
blood on the carpet a serious disagreement or its aftermath; used hyperbolically to suggest that there has been bloodshed.
blood, toil, tears and sweat Winston Churchill's summary of what in May 1940 he could offer the country for its immediate future, in the words, ‘I have nothing to offer but blood, toil, tears and sweat.’
blood will have blood killing will provoke further killing. Recorded as an English saying from late Middle English, but ultimately, the saying refers to Genesis 9:6, ‘Whoso sheddeth man's blood, by man shall his blood be shed.’
blood will tell family characteristics or heredity cannot be concealed. Saying recorded from the mid 19th century.
first blood the first point or advantage gained in a contest. Also literally, ‘the first shedding of blood’, especially in a boxing match or formerly in duelling with swords.
make one's blood curdle fill one with horror. Like the alternative make one's blood run cold, originating in the medieval physiological scheme of the four humours in the human frame (melancholy, phlegm, blood, and choler). Blood was the hot, moist element, so the effect of horror or fear in making it run cold or curdling (solidifying) it was to make it unable to fulfil its proper function of supplying the body with vital heat or energy.
you cannot get blood from a stone often used, as a resigned admission, to mean that it is hopeless to try to extort money or sympathy from those who have none. Recorded from the mid 17th century, but a late Middle English poem by Lydgate has the related ‘Harde to likke hony out of a marbil stoon, For there is nouthir licour nor moisture’,

See also baptism of blood, blue blood, in cold blood, stir the blood.