Synonym of slash as the forward slash ⟨/⟩ and sometimes also its proscribed sense inclusive of the backslash ⟨\⟩.
The proofreader's mark resembling a slash ⟨ / ⟩ or vertical bar ⟨ | ⟩ placed after a note in the margin to indicate that it should replace the item(s) struckthrough in the running text or to separate it from other margin notes.
The ⟨L⟩ or pipe ⟨|⟩ mark formerly used to divide integers from decimals.
The line between regions having different magnetic fields.
The boundary separating two modes of behavior in a differential equation.
A terminator: a line on a partially-illuminated surface separating the lit and shaded regions.