The Collaborative International Dictionary of English v.0.48:

Allision \Al*li"sion\, n. [L. allisio, fr. allidere, to strike
   or dash against; ad + laedere to dash against.]
   The act of dashing against, or striking upon.
   [1913 Webster]

         The boisterous allision of the sea.      --Woodward.
   [1913 Webster]

Bouvier's Law Dictionary, Revised 6th Ed (1856):

ALLISION, maritime law. The running of one vessel against another. It is
distinguished from collision in this, that the latter means the running of
two vessels against each other; this latter term is frequently used for
allision.