Lewis & Short

2. laetus, i, m., in late Lat., a foreign bondman who received a piece of land to cultivate, for which he paid tribute to his master, a serf, Amm. 20, 8, 13; Eum. Pan. 21, 1.
Hence,

  1. A. laeta, ōrum, n., the land so cultivated, Cod. Th. 7, 20, 10.
  2. B. laetĭcus, a, um, adj., of or belonging to a laetus: laeticae terrae, Cod. Th. 13, 11, 9.