frid-hengest

frid-hengest, m.n: of uncertain meaning but ‘hengest’ is definitely ‘horse’; one suggestion is ‘horse-horse’ (tautological); less likely are ‘beautiful-horse’, ‘peace-horse’ or ‘war-horse’. (FRID-HENG-gest / ˈfrɪd-ˌhɛŋ-gɛst)

Medieval manuscript image of blue horse with spots.
Bestiary; England, 1220-1240; Cambridge University Library, Kk.4.25, f. 59r. [cudl.lib.cam.ac.uk]

lempedu

lempedu, f.n: a lamprey. (LEM-peh-duh / ˈlɛm-pɛ-dʌ)

Medieval manuscript illustration of a brown eel coiled up with a funny sort of grimace on its face.
Eel in Der Naturen Bloeme (I realise this may not be specifically a lamprey… feel free to share if you have a medieval lamprey pic); Flanders, c. 1350; Koninklijke Bibliotheek, KB, KA 16, f. 117r. [galerij.kb.nl]