Real Dictionary

outsize
Outsize or outsized things are much larger than usual or much larger than you would expect.

outsize in American English
a size varying from the usual standard; odd size; esp., an unusually large size
of nonstandard size; esp., unusually large
adjective: being unusually or abnormally large, heavy, extensive, etc
noun: an uncommon or irregular size, esp. one larger than average

outsize in British English
adjective: very large or larger than normal
noun: something outsize, such as a garment or person