It can be argued what a continent is or is not. The traditional definition was artificially tortured to allow a cultural Europe to be defined as a geological concept (it is really more a peninsula of the Euro-Asian Continent).
However we can definitely say what a Continent is NOT - and it is not this...
One QUARTER of the size of Madagascar. Now Madagascar is a mad big island, but still small compared to the smallest Continent, Australia. Something that is one quarter of that size, hidden below or above the ocean, in not a Continent.
If you think so, I have a Continent off Connecticut and bridge that leads to it for sale.