labrum
From ZooTerms (Dictionary of Invertebrate Zoology)
labrum (noun; plural labra; Latin labrum, lip): 1. A lip or edge.
2. (Arthropoda: Chelicerata) In Araneae, has been incorrectly used for the labium.
3. (Arthropoda: Crustacea) The unpaired outgrowth arising in front of the mouth and often covering it; upper lip.
4. (Arthropoda: Insecta) The upper lip located below the clypeus and in front of the other mouth parts.
5. (Arthropoda: Trilobita) The hypostoma of a trilobite fossil.
6. (Echinodermata: Echinoidea) A flap of the interambulacrum which projects over the ventral peristome.
