Using the word 'tiffin' to refer to a lunch box

In "Indian English" (whatever that means) the word 'tiffin' is used to refer to lunch boxes in south Asia. Please feel free to Google the word if you want a picture of what such lunch boxes look like.

I recently, out of habit, used the word in the US and no one knew what it meant. I was asked if it's a Hindi word or an English word. That got me thinking. I always assumed it was an English word but after quick Google search it does not seem like it.

So my question is does any other place use the word 'tiffin'? If not, how did it take hold in south Asia? Is it an archaic British word that stuck in India following the colonial rule?

It is an Indian English term, probably from BrE old slag term tiffing, meaning take a little drink:

In the British Raj, where the British custom of afternoon tea was supplanted by the Indian practice of taking a light meal at that hour, it came to be called tiffin. It is derived from English colloquial or slang tiffing meaning to take a little drink, and had by 1867 become naturalised among Anglo-Indians in the north of the country to mean luncheon.

(Wikipedia)

The ODO suggests that its origin is from a dialectal term meaning “sipping”:

Tiffin:

Early 19th century: apparently from dialect tiffing ‘sipping’, of unknown origin.

World Wide Words has a reasonable description of the word tiffin's origin.

More than any other word, tiffin, meaning lunch or any light meal, evokes British India.

It entered the language at the very beginning of the nineteenth century, perhaps because the English fashion for eating dinner mid-afternoon was giving way under the influence of the Indian climate to a main meal taken later in the day, requiring a lighter midday meal and a name for it. Why the much older luncheon wasn’t used isn’t clear. Instead, the English in India borrowed tiffing, an old English dialect or slang word for taking a little drink or sip. (I forbear from suggesting that the habit among some sahibs of drinking their lunch had something to do with the popularity of the term.) The word is still widely used in India for any hot light meal or snack taken at any time during the day.

In Mumbai (formerly Bombay), the term tiffin-wallah is sometimes heard, though the more common term is dabbawallah. Lunches are cooked at home by workers’ wives and then transported, often by train, perhaps 20 or 30 miles to their husbands' workplaces, each three-tiered tiffin-carrier or dabba probably passing through several hands in a sophisticated and efficient cooperative process. Those who deliver the meals by bicycle on the final stage of their journeys are the tiffin-wallahs or dabbawallahs.

An early example of tiffin is from a guide book, Cordiner’s Ceylon, of 1808: “Many persons are in the habit of sitting down to a repast at one o’clock, which is called tiffen, and is in fact an early dinner”.

I've never heard of it before, from Australia.

Wikipedia, says "tiffin" is:

Tiffin, a light meal eaten during the day.

In the disambiguation page. In the article it says:

Tiffin is an Indian English word for a type of meal. It can refer to the midday luncheon or, in some regions of the Indian subcontinent, a between meal snack, or in South Indian usage, a light breakfast.

In the introduction it does not mention it as a lunch-box as you say, however further down:

In Mumbai, a school-going child's lunch box is fondly called a Tiffin box.

In addition, the lunch boxes are themselves called tiffin carriers, tiffin-boxes or just tiffins.

There is also an article for tiffin carrier. It looks like this:

From South Asia, they spread to and now are widely used in India, Indonesia, Malaysia, Thailand and Singapore as well.

In dictionaries there are the following definitions:

A meal at midday, especially in South Asia.
American Heritage Dictionary

(Cookery) (in India) a light meal, esp one taken at midday
Collins Dictionary

noun
1.lunch.
verb (used without object)
2.to eat lunch. verb (used with object)
3.to provide lunch for; serve lunch to.
Dictionary.com

Wikipedia lists tiffin as also being the container for the tiffin, but none of the dictionaries I've listed do, they say it is the tiffin itself, (the food).

Sources:
Wikipedia article on tiffin
Wikipedia article on tiffin box

It's not completely unknown in the UK. Apart from the cake similar to rocky road, I've known a very good Indian lunch takeaway place called tiffin (and seen a few others similarly named). I have seen Indian tiffin carriers for sale, but only in places run by/for people of Indian heritage.