Webster’s Revised Unabridged Dictionary · 1913
Lambdoid
Lamb′doid (·doid), a. [Gr. λαμβδοειδής, λάμβδα the letter lambda (Λ) + εἷδος shape.] Shaped like the Greek letter lambda (Λ); as, the lambdoid suture between the occipital and parietal bones of the skull.