∥

∥

1. (geometry) Parallel lines.

   ${\displaystyle AB\parallel CD}$ indicates that line AB is parallel to line CD

2. (mathematics) Of strings, lists, vectors, or matrices, concatenated with.

   ${\displaystyle [0,1,2]\parallel [3,4,5]=[0,1,2,3,4,5].}$

• ∦
• ⟂

• ⋕
• ⩨

• ‖ (caesura)
• ⧺ (“concatenated with”)