1) Polyvinyl acetate 2) Polyvinyl resin 3) Vinyl polymer 4) Vinyl resin 
Positive Vorticity Advection.
Polyvinyl Alcohol, A water soluble filament used as 3D printing material. Often PVA is used as support material.
The Plant Variety Act. See U.S. Department of Agriculture.
Paralyzed Veterans of America
A water based type of adhesive 
Positive Vorticity Advection. Advection of higher values of vorticity into an area, which often is associated with upward motion (lifting) of the air. PVA typically is found in advance of disturbances aloft (i.e., shortwaves), and is a property which often enhances the potential precipitation.
Poly Vinyl Alcohol 
Polyvinyl acetate, a manmade resin used as a paint medium and in varnish.
PVA is a type of plastic: polyvinyl acetate, which is commonly used to make glue hence: PVA glue, which is commonly referred to simply as 'PVA'. PVA glue is commonly used by woodworkers and therefore gets referred to as 'wood glue'. It is also known as 'white glue' because it is white when wet (but dries clear). 'Elmer's White Glue' is a well known...