Masuk angin is a uniquely Indonesian thing that is hard to explain. Masuk angin literally translates as “wind goes in”, and it is a danger whenever the wind can go into you, like when you don’t wear longsleeves on a motorbike, or in the mountains, or if you are an under-dressed tourist in the street. Masuk angin makes you feel off, sometimes dizzy, sometimes indigestion (gas, bloating, burping), sometimes like a hangover with a headache, sometimes just a bad mood. Masuk angin is an acceptable excuse to escape any social or religious obligation. Every Indonesian understands what masuk angin is and respects the necessity of it.
I myself don’t entirely believe masuk angin is a real thing, however I understand what it means when E has it, and I have used it as an excuse for myself as well. I think of masuk angin more as a useful social convention than as a specific ailment, and in that sense I believe in it and also like it.
There are some interesting remedies for masuk angin, such as rubbing someone’s back with a vintage coin in a branching pattern until red marks form, supposedly releasing the angin/wind. At home we drink warm water to assuage it, or rub the back or other affected area with minyak kayu putih/cajeput oil.