means an official endorsement on a passport that grants the holder permission to enter, stay in, or leave a particular country.

from From the Latin 'charta visa,' meaning 'paper that has been seen' — 'visa' being the feminine past participle of 'videre,' to see (a cousin of words like 'vision' and 'visible'). The idea is delightfully literal: a document an official has laid eyes on and approved. The word reached English through French in the 19th century, carrying that same sense of a paper inspected and waved through.