noun. A rounded edge, corner, or projection, as on a stairstep or paving stone.

noun. An overgrown hard clam or quahaug, Mercenaria, too coarse for use.

noun. rounded ceramic trim, especially in masonry and ceramic tile

noun. a small carpenter's plane with the cutting edge near the front

"Unfortunately, it soon became clear that we did not have the "bullnose" tiles (with one rounded edge) needed for some outside corners."

carpenter's plane  plane  woodworking plane