Definition of au pied de la lettre in English:
au pied de la lettre
adverb
Exactly, down to the last detail; literally. Compare to the letter.
Origin
Mid 18th century; earliest use found in Charles Jarvis (1675–1739), portrait painter and translator. From French au pied de la lettre, lit. ‘to the foot of the letter’ from au to the + pied foot + de + la the + lettre.
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