WordNet sense 1 (a line determining the limits of an area):

bound, boundary

WordNet sense 2 (the boundary of a surface):

border

WordNet sense 3 (the attribute of urgency):

sharpness

WordNet sense 4 (a strip near the boundary of an object):

margin, margin

WordNet sense 5 (advance slowly, as if by inches):

inch

WordNet sense 6 (lie adjacent to another or share a boundary):

abut, adjoin, march, butt against