Entry 1 sense Webster, 1913 Lampern · Lam·pern · IPA /ˈlæmpəɹn/ 01 n. The river lamprey (Ammocœtes fluviatilis syn. Lampetra fluviatilis). 1. The river lamprey (Ammocœtes fluviatilis syn. Lampetra fluviatilis).(Zool.)