Lewis & Short

com-păciscor (conp-) or -pĕcis-cor, pactus or pectus, 3, v. dep.,

  1. I. to make an agreement, form a compact with one (only in temp. perf. and partic., and rare): si sumus compecti, Plaut. Ps. 1, 5, 129: mecum matrimonio compecta sit, id. Cist. Fragm. Mai, p. 17, v. 11.
    Hence,
  2. II. P. a. as subst.: compactum (conp-) or compectum (conp-), i, n., an agreement, only in abl. sing.: compacto (compecto, Cic. Scaur. 5, 8 B. and K.), according to agreement or concert, in accordance with a previous compact, Afran. ap. Charis. p. 177 P.; Cic. Scaur. l. l.; id. Att. 10, 12, 2 Orell. N. cr.: conpecto, Liv. 5, 11, 7.
    In a similar sense: de conpecto, Plaut. Capt. 3, 1, 24; 3, 1, 29; id. Ps. 1, 5, 126; and: ex compacto, Suet. Caes. 20; Cod. Just. 7, 53, 3.