Lat. In Roman law. An oath, as being a very sacred thing; more particularly, the oath taken by soldiers to be true to their general and their country. Alnsw. Lex. In one of the formal methods of beginning an action at law (legis actiones) known to the early Roman jurisprudence , the sacramentum was a sum of money deposited in court by each of the litigating parties, as a kind of wager or forfeit to abide the re- 8ACRAMENTUM 1051