Lewis & Short

† cērōma, ătis, n.

    (
  1. I. abl. plur. ceromatis, Plin. 35, 13, 47, § 168; acc. plur. ceromas, Arn. 3, 114), = κήρωμα, an ointment for wrestlers, much used in the time of the emperors, Plin. l. l.; 28, 4, 13, § 51; Mart. 4, 19; 7, 32; 14, 50.
  2. II. Meton.
    1. A. The place for wrestling: in ceromate sedere, Sen. Brev. Vit. 12, 2; Plin. 35, 2, 2, § 5.
    2. B. The ring, the combat, Plin. 29, 1, 8, § 26; Mart. 5, 65, 3 (in Plin. Val. 1, 25 fin., ceromata is perh. = canceromata, a swelling, tumor).