The Collaborative International Dictionary of English v.0.48:

Accubation \Ac`cu*ba"tion\ ([a^]k*k[-u]*b[=a]"sh[u^]n), n. [L.
   accubatio, for accubitio, fr. accubare to recline; ad +
   cubare to lie down. See Accumb.]
   The act or posture of reclining on a couch, as practiced by
   the ancients at meals.
   [1913 Webster]