An obsolete verb meaning to disturb, trouble, or assault like a storm; to pester or harass.
From em- + pest (originally from Latin pestis, plague or curse). The em- prefix intensifies the verb form, creating an image of being swamped by pests or troubles.
This word is so vanishingly rare that it appears in maybe one or two medieval texts—it's a linguistic fossil from a time when English speakers felt free to combine em- with almost any word to create new verbs.
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