constratum
Could not find Constratis in Logeion dictionaries.
Constratis Noun: neuter ablative plural, Noun: neuter dative plural of constratum
constrātum, i, n., v. 1, consterno, I. 2.
cōnstrātum, ī, n., s. 1. cōn-sterno no. I, a, β.
cōnstrātum, (15) ī, n. (constratus), plancher : constrata pontium Liv. 30, 10, 14, le plancher des ponts ; constratum puppis Petr. 100, 6, pont dʼun navire.
Constrātum
In general, any flooring made of planks. Thus constratum navis, “the deck of a ship” (Petron.100); constratum pontis, “a bridgeway” (Livy, xxx. 10), etc.