LATIN DICTIONARYLexicon Latīnum
English → Latin

“index” in Latin

The English word index itself goes back to Latin in, through index.

Riddle & Arnold A Copious and Critical English–Latin Lexicon, 1864

index
Of a book, index (for which catalogus is late). An alphabetical index of (e.g., rivers), amnium in litteras digesta nomina (Vib., Sequ.): to enter into an index, in indicem referre: indexs, indices librorum.
Hand of a watch, gnomon (on a sun-dial): virgula horarum index (general term, after Plin., 18, 37, 67).
IMPROPR., imago: index (the former as reflecting anything; the latter as indicating or betraying its nature: e.g., imago animi vultus, indices oculi, Cic.): janua (as opening and disclosing it to view: frons, quae est animi janua, Cic.).
Index
Index, -icis (m.)

Quick answer

What is the Latin word for index?
The usual Latin words for “index” are index, gnōmōn, imāgō; also iānua. The right choice depends on the sense; see the distinctions below.

Entry from J. E. Riddle & T. K. Arnold, A Copious and Critical English–Latin Lexicon (rev. C. Anthon, New York: Harper, 1864), digitised by Fergus J. P. Walsh, CC BY-SA 4.0; Latin markup adapted by latindictionary.co.