Past tense of arid (though rarely used as a verb); made or became extremely dry.
From arid (Latin aridus, 'dry') + -ed (past tense suffix). The verbal form is archaic or technical.
While 'arid' is usually an adjective describing deserts, turning it into a verb 'to arid' is so rare that most dictionaries don't list it—but it shows how English speakers can theoretically verb almost any adjective when needed.
Complete word intelligence in one call. Free tier — 50 lookups/day.