An opening or gap, particularly used in anatomy or geology to describe a space or fissure.
From Latin 'hiatus' meaning opening or gap. The term entered English through medical and scientific terminology in the 17th century.
You've heard of a 'hiatal hernia'—that's when something pokes through a 'hia' (opening) in your diaphragm, showing how this ancient Latin term still describes real body problems.
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