Term: Mainsail Image: [{"name":"images\/public\/dictionary\/Mainsail_0kcx53c2.png","usrName":"Mainsail.png","size":122164,"type":"image\/png","thumbnail":"images\/public\/dictionary\/thMainsail_fwrymkr1.png","thumbnail_type":"image\/png","thumbnail_size":50414,"searchStr":"Mainsail.png,!:sStrEnd"}] Definition: <div>The largest regular sail on a sailboat.</div><div><br></div>