The Collaborative International Dictionary of English v.0.48:

motorcade \motorcade\ n.
   a procession of people traveling in motor cars.
   [WordNet 1.5] Motor car

WordNet (r) 3.0 (2006):

motorcade
    n 1: a procession of people traveling in motor cars

Moby Thesaurus II by Grady Ward, 1.0:

20 Moby Thesaurus words for "motorcade":
   caravan, cavalcade, column, cortege, dress parade, flyover,
   funeral, line, march past, mule train, pack train, parade, pomp,
   procession, promenade, review, skimmington, stream, string,
   train