“And hath made of one blood all nations of men.”- Acts xvii. 26.
Blood thicker than water. Relationship has a claim which is generally acknowledged. It is better to seek kindness from a kinsman than from a stranger. Water soon evaporates and leaves no mark behind; not so blood. So the interest we take in a stranger is thinner and more evanescent than that which we take in a blood relation.
“Weel! blude's thicker than water. She's welcome to the cheeses and the hams just the same.” —Sir W. Scott: Guy Mannering.
A Prince of the Blood. One of the Royal Family. Bad blood. Anger, quarrels; as, It stirs up bad blood. It provokes to ill-feeling and contention. Blue blood. (See under Blue.)
Young blood. Fresh members; as, “To bring young blood into the concern.” In cold blood. Deliberately; not in the excitement of passion or of battle. It makes one's blood boil. It provokes indignation and anger.
It runs in the blood. It is inherited or exists in the family race.
“It runs in the blood of our family.” —Sheridan: The Rivals, iv. 2.
My own flesh and blood. My own children, brothers, sisters, or other near kindred. Laws written in blood. Demades said that the laws of Draco were written in blood, because every offence was punished by death.
The field of blood. Aceldama (Acts i. 19), the piece of ground purchased with the blood-money of our Saviour, and set apart for the burial of strangers.
The field of the battle of Cannæ, where Hannibal defeated the Romans, B.C. 216.
Blood of our Saviour. An order of knighthood in Mantua; so called because their special office was to guard “the drops of the Saviour's blood” preserved in St. Andrew's church, Mantua.
Blood and iron policy i.e. war policy. No explanation needed.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894