In my native language, the stuff is called "aluminium foil".
In English, I always heard people use the phrase "tin foil" for that. I adopted that phrase thinking that despite the foil being made of aluminium (and not tin as it used to be) this is what people call it.
Recently a native American English speaking person took the phrase literally and wondered why I would want tin foil, because aluminium foil is much more common these days…
I checked the wikipedia article on the matter and found this quote:
Actual tin foil was superseded by cheaper and more durable aluminium foil after World War II. Despite this, aluminium foil is still referred to as "tin foil" in many regions.
What regions use the term "tin foil" what use "aluminium foil"? Does the majority of English speakers understand "tin foil" as "aluminium foil"?
I'd happily adopt the more correct phrase "aluminium foil", but a-lu-mi-ni-um is quite a mouth full. Even in my native language it is commonly abbreviated with just "alu". IS there something like that in English? I think the shortness of tin is what kept people using it.
What's the best phrase to refer to aluminium foil?
Best Answer
Several commenters have wondered if the commonality of "tin foil" in the ngrams in other answers is affected by the phrase "tin foil hat" specifically. According to the ngram below, I would say not--as "tin foil hat" is quite a flat line compared to the others.
Now, whether or not the prevalence in modern-day speaking of "tin foil" is affected by the cultural term "tin foil hat" is another question; one we don't really have documentary evidence to support or disprove. I will say that from my AmE perspective, "tin foil" sounds distinctly British, and personally I say "aluminum foil" about half the time, and simply "foil" the rest of the time. It surprises me to see many AmE speakers weighing in as "tin foil" users. It's not something I hear in my area (north Texas) often.
So! Clearly this one is anecdotal, and varies highly among individual respondents (and doesn't even seem to have a high regional correlation). So I would say this: if you prefer "aluminum", and aluminum is technically scientifically correct, and everyone will understand you when you say it... That sounds like a lot of good evidence to go with it :) As long as you understand "tin foil" when you hear it, I don't see any reason to use it yourself if you don't want to.