i feel like either you have to not call india a subcontinent or you have to also call something else a subcontinent. doing neither is not reasonable
europe is the obvious candidate but nobody does it! very silly. europe and india are the same in so many ways...
there's the indian subcontinent: a geological region containing the indian peninsula, bounded by the himalayas and the thar desert, or approximately the ganges and the indus river
there's the european subcontinent: a geological region containing the scandinavian peninsula, the iberian peninsula, and other regions north of the mediterranean, east of the atlantic, and bounded by the ural mountains, caucasus mountains, and various inland seas
there's the arabian subcontinent: a geological region containing the arabian peninsula, bounded by the arabian tectonic plate
there's the horn of africa, a geological region that is a peninsula, just to the south of the arabian peninsula
really the key here is that they're huge peninsulas of over a million square kilometres, often bounded by some major geological or cultural border, often with other notable features within them
the largest of these by far, the european subcontinent of over ten million square kilometres, itself contains multiple large peninsulas approaching a million square kilometeres, so maybe it ought to be split up and treated as a collection? like how southeast asia is a collection of large islands and archipelagos millions of square kilometres in size, bounded at one extreme by australasia which is nearly ten million square kilometres in size
