Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
† trĕchĕdīpnum, i, n. (sc. vestimentum), = τρεχέδειπνον (running to a banquet), a light garment worn at table by parasites, Juv. 3, 67 (trechedipna vestimenta parasitica currentium ad cenam, Schol.).