Two Lights Are Better Than One

An extra fun fact from my exploration of alleviate on etymonline.com yesterday was a discovery about the convergent derivation of the word light.

While it would seem as though its meaning as in not heavy and its meaning as in not dark could come from the same root, they do not. 

The not-heavy meaning, as I discussed yesterday, comes from the Proto-Indo-European root *legwh-, "not heavy, having little weight." But the not-dark meaning comes from the PIE root *leuk-, "light, brightness."

The two converged a long time ago in the Anglian and Saxon leht, and then shifted to the Old English leoht, which became light. Etymonline.com says, "The -gh- was an Anglo-French scribal attempt to render the Germanic hard -h- sound, which has since disappeared from this word."

I'm still trying to wrap my head around the idea that the two words could be different. I'm not there yet.