Lemon and Lime Are the Same Word (Kind Of)
You've been using two words this whole time. One word would have been enough.
"Lemon" and "lime" are doublets. They come from the same ancient source, took different roads through a dozen languages, and arrived in English as neighbors. As if they crossed an ocean on separate ships and ended up living on the same street.
It Starts Somewhere You Wouldn't Expect
Forget French. Forget Arabic. Forget even Sanskrit for a second.
The root of "lemon" and "lime" is Austroasiatic. A language family spoken in South and Southeast Asia, predating Sanskrit by centuries. Mundari, a Munda language still spoken today in Jharkhand, India, has the word lembu for citrus. That word, or something very like it, got borrowed into Sanskrit as nimbū.
Sanskrit handed it to Hindi and Urdu. In Hindi it became nīmbū. In Urdu, written in a different script, it's نیمبو. Same word, different alphabets. Same citrus, different page.
If you've ever had nimbu soda in India, that's the word. A lime-and-soda drink you find everywhere. The name is older than almost anything you can order at a bar.
The Great Fork
Here's where it gets good.
Persian borrowed from Hindi and produced lēmū or līmū. Arabic then borrowed from Persian and got two forms. One was laymūn. Another was līma.
These two Arabic forms took separate exits.
Laymūn went through Old French as lymon and became English "lemon."
Līma went through Spanish as lima, then French, and became English "lime."
The fruit split in two. The word split in two. You got twice the citrus for the price of one etymological ancestor.
Meanwhile, Across the Pacific
There's a parallel story happening thousands of miles away.
Proto-Malayo-Polynesian, the ancestor of languages across Southeast Asia and the Pacific, had *limaw for citrus. Malay limau descends directly from it. So does Gujarati lību.
In Fijian and Polynesian languages, that same root shows up as moli. Different sound, same fruit, same ancient word. The citrus traveled with people across half the world's ocean.
This branch didn't directly give English "lime" or "lemon." But it's the same word moving through a completely different corridor. Two rivers from one mountain.
Why Word Nerds Should Care
Doublets are rare. They happen when one language borrows the same word twice, through different routes, at different times, and both forms survive with slightly different meanings.
"Lemon" and "lime" are technically different fruits. But etymologically? You've been saying the same thing twice. Like playing ZEAL and ZEALOUS in the same Scrabble game and wondering why they feel related.
The next time someone asks you if lime and lemon are really that different, you can say: not originally. One word. Two trips. Same ancient grove in what is now Jharkhand.
Language is just citrus that took the long way home.
Source: Languagehat