Plural of fraenulum; very small restraining bands, ligaments, or anatomical structures that limit movement.
From Latin fraenulum (diminutive of fraenum), combining fraenum (bridle) with -ula (diminutive suffix). The double plural shows Latin anatomical naming.
Scientists love Latin diminutives because they let you nest meaning—a fraenum is a small bridle, and a fraenula is a tiny-tiny bridle, letting doctors describe structures at different scales.
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