Ok this has me a bit confused
Curry is a dish but while MOST western curry (from Curry Powder) are the same few ingredients... Proper curry dishes can have any multitude of spices from around the world in any combination with 5-20 spices.
But... What are the rules for something to count as a Curry? I find this impossible to research... Only that it needs to be at least a 5 spice blend.
"Curry" in English is a somewhat ambiguous term, which generally speaking can refer to almost any dish cooked in a spiced sauce, and even the sauce requirement is a bit iffy, as in Thai style dry curries. It is predominantly used to refer to styles of food eaten in the Indian subcontinent, Southeast Asia, parts of Africa, and the Caribbean. The styles it refers to are somewhat different between, and even within the regions I mention here, though most can trace their origins back to the Indian sub-continent. 'Curry powder' can refer to a pretty wide variety of spice blends as well. Most blends using the name contain a fair bit of turmeric, but can vary pretty widely in the selection and amounts of other spices. The word curry is usually believed to be an Anglicisation of the Tamil word 'kari' (meaning sauce), which was initially used by British people living in India to refer to the wide variety of Indian foods consisting of meat or vegetables cooked in a heavily spiced sauce, and was eventually adopted to refer to superficially similar dishes throughout the British empire and other lands the Brits visited.
As far as what it takes to be called curry? Basically, if it involves cooking meat or vegetables in a strongly seasoned sauce or frying meat/vegetables with a 'curry paste', and the person who originally created the dish wants to call it curry or it's from one of the regions with traditional foods commonly referred to as curry, then it probably qualifies.
edit: I forgot to mention, almost all dishes referred to as curry are traditionally served with some kind of starch, such as bread, noodles, rice, or other cooked grains.