The Dow and the Nikkei

• Catalogues
• Back-of-the-book conveniences
• Book lists
• Textbook adjuncts
• Signs I’d since altered
• Hands pointing to text in square after cubes

WordNet Word definitions in WordNet
n. a numerical scale used to compare variables with one another or with some reference number a number or ratio (a value on a scale of measurement) derived from a series of observed facts; can reveal relative changes as a function of time [syn: index number ...

Douglas Harper's Etymology Dictionary Word definitions in Douglas Harper's Etymology Dictionary
according to OED, the plural form of index preferable in scientific and mathematical senses of that word.

Wiktionary Word definitions in Wiktionary
n. (en-irregular index nodot=1) (gloss: when used in the sense of a key to locate an element in a list, vector or matrix in computing or mathematics)