dictionary

The English word dictionary goes back to Medieval Latin dictionarium, a book of words. John of Garland used Dictionarius as the title of a Latin learning text in Paris around 1225. That title came from Latin dictio, meaning a saying, expression, or word. The suffix turned the base into the name of a collection.

Classical Latin dictio came from dicere, to say. Roman writers used dictio for speech, wording, and formal utterance. In the schools of medieval Europe, the sense moved toward listed vocabulary and lexical teaching. By the 13th century, dictionarium could name a book arranged to explain words.

French developed dictionnaire, recorded in the 16th century, from the same Latin source. English borrowed the learned form in the 1500s as dictionarie and dictionary. The word spread with printing, grammar teaching, and bilingual reference books. By the time of Samuel Johnson's Dictionary in 1755, the modern spelling and sense were settled.

Today dictionary names a reference work that explains words, meanings, pronunciations, or translations. The form is still visibly tied to saying and speech through its Latin ancestry. What began as a schoolbook title became the standard English name for a lexicon. The history is unusually well dated because the medieval book title survives.