Earlier this week I created the index for my eponym book, a thrilling task as I’m sure you can imagine. It got me thinking about the word itself. Clearly it has some Latin roots going on, but where exactly do we get index from?
The word in means “towards” in Latin and an index does point us towards information so that makes sense and also links it to the index (or pointer) finger.
It expands to indic- as prefix (still in Latin) to mean “forefinger or sign”. That combines with either dicere or dicare to give us index. Dicere means “to say” and dicare means “to make known”. Taken together that gives us index as meaning “to point the way and to make known”, that’s pretty good fit for the modern use of the word, or finger.
Index reached middle English by the early 1400s and has retained its meaning since although an index will mean different thing to people working in different fields. An index is vital in databases, for example, where it points to the data. They are part of scientific instruments. We have a price index in economics and sadly an index of forbidden books within religious history. The interesting thing is that index in all these cases has the same core meaning – it’s a way to point out the relevant information. Most words I explore here change over a 600 year history, but index is still pointing the way.
Until next time happy reading, writing, and wordfooling,