Langsat

It took me FOREVER to find the English name of this fruit someone brought me recently. I don't even know the Vietnamese name. I know it's delicious and refreshing though!
Superficially the langsat resembles a longan but the taste and interior structure is nothing alike. The langsat comes apart in slices, the texture is again similar to lychees or longans but the aftertaste is all grapefruit or pomelo.