India, May 24 -- There are some words so simple, it is possible they will never mean anything else: pain, rain, love.

More complex terms can have quite the journey, nodding backwards, eternally, to their complicated and often-distant roots. Let's start with one of my favourites.

The Arabic "al-kuhul" was originally "a powder used to darken the eyelids". This of course is where we get the word kohl. But, in laboratories of the time, the term began to be used to refer to any fine powder. Then it began to be used for any refined liquid (typically purified through distillation). Soon, it became the term for all distilled liquids.

From there, it was a short skip to, you guessed it: alcohol.

Fast-forward a bit for an intriguing one. Theriak...