1) Armchair protector 2) Chair upholstery item 3) Cloth covering 4) Domestic implement 5) Furniture protector 6) Sofa protection 7) Top for some convertibles 
A slipcover (also called loose cover) is a fitted protective cover that may be slipped off and on a piece of upholstered furniture. Slipcovers are usually made of cloth. Slipcovers slip on and off, they come fresh, and may be removed for seasonal change, cleaning, moving, or storage. Slipcovers are sometimes defined as `clothing for furniture.` .....
an easily removable fabric cover for a chair or couch
[n] - a removable fitted cloth covering for upholstered furniture
noun a removable fitted cloth covering for upholstered furniture