The phrase "to stain the canvas" means to make a permanent mark or a lasting impact on something, typically in a negative or undesirable way. Full definition
This six part work involved several hundred feet of paint stained canvas, and was commissioned for the exterior walls of two adjacent wings of the museum. (americanart.si.edu)
Measuring 10 feet high by 75 feet long, the vivid, color - stained canvas hangs suspended from the ceiling. (mmoca.org)
The Newport Street exhibition is the first major show since Hoyland's death in 2011 and will reaffirm his status as an important and innovative force within international abstraction, providing new insights into the way in which his work evolved from the huge colour - stained canvases of the 1960s, through the textured surfaces of the 1970s to the more spatially complex paintings of the early 1980s. (johnhoyland.com)