Definition of downsides:
(n) :
A disadvantageous aspect of something that is normally advantageous.
(n) :
A downward tendency, especially in the price of shares etc.
(n) :
The side of something that is at the bottom, or that is intended to face downward.
(n) :
A number of places in England:
(n) :
A southern suburb of Dunstable, Central Bedfordshire district, Bedfordshire (OS grid ref TL0320).
(n) :
A suburb of Eastbourne, East Sussex (OS grid ref TV5999).