Lewis & Short

concrētĭo, ōnis, f. [concresco].

  1. I. Abstr., compacting, uniting, condensing, congealing (opp. liquor), Cic. Univ. 14 init.: individuorum corporum concretio, id. N. D. 1, 25, 71: prava corporis, Firm. Math. 1, 3: substantiarum, Tert. Anim. 52.
  2. II. Concr., materiality, matter: (deus) mens soluta quaedam et libera segregata ab omni concretione mortali, Cic. Tusc. 1, 27, 66; cf. Lact. 1, 5.