. "tick mark"@en . . . . "A tick mark is a line segment that is spatially positioned perpendicular to the axis of a statistical graph and indicates the position of a specific numeric value (which may be indicated by an adjacent value label) on a value axis, or is one of a pair of tick marks that delineates the boundary of a categorical value (which may be indicated by an adjacent category label) on the categorical axis."@en . "SIO_000513" .