1) Boat type 
A monohull is a type of boat having only one hull, unlike multihulled boats which can have two or more individual hulls connected to one another. ==Fundamental concept== Among the earliest hulls were simple logs, but these were generally unstable and tended to roll over easily. Hollowing out the logs into a dugout canoe doesn`t help much unless t....
A boat that has only one hull.
a boat with a single hull
(of a vessel) having a single hull.