What does “Having turnip blood” mean?
To have turnip blood is to be without vigor, by extension to lack courage.
Prosper Mérimée, who could not be blamed for having turnip blood, had a pronounced taste for mystification. In 1828 he published a play “La famille de Carvajal” whose preface contains the text of a letter signed by a certain Diego Rodriguez de Castaneda y Palacios.
“…. for me all these heroes of tragedy are only phlegmatic philosophers, without passions, who have only turnip juice instead of blood in their veins, of these people finally whose head would turn by tightening a topsail….” .
This image therefore appearing in Mérimée in 1828, was later (late 19th, early 20th century) lexicalized in the form “to have turnip blood in the veins” to qualify an anemic person, whose blood is supposed to be pale (the color of turnip juice) for lack of red blood cells.
In Gustave Armand Rossignol's slang dictionary (1901) the meaning linked to cowardice is attested: “he who is not brave has turnip blood or white liver”.
In contemporary French, the expression “to have turnip blood in the veins” has become “to have turnip blood”
