look at all parts of (something) carefully in order to detect some feature.
he raised his binoculars to scan the coast
cause (a surface, object, or part of the body) to be traversed by a detector or an electromagnetic beam.
their brains are scanned so that researchers can monitor the progress of the disease
analyze the meter of (a line of verse) by reading with the emphasis on its rhythm or by examining the pattern of feet or syllables.
By the end of the term, several students still could not scan a basic line or write in metre.