The term Parallel has a number of important meanings:
Parallel (geometry) occurs in geometry. If two lines or planes are parallel, then every point on one is located exactly the same minimum distance from the other line or plane.
Parallel computing is the simultaneous execution of the same task (split up and specially adapted) on multiple processors in order to obtain faster results.
In electronics, components are said to be "in parallel" if current branches to flow through both simultaneously, as against "in series" where the current flows through first one, then the other, along a single path.