Source : Webster's Revised Unabridged Dictionary (1913)

Catchweed \Catch"weed`\, n. (Bot.)
   See {Cleavers}.

Source : WordNet®

catchweed
     n : annual having the stem beset with curved prickles; North
         America and Europe and Asia [syn: {cleavers}, {clivers},
         {goose grass}, {spring cleavers}, {Galium aparine}]