there is no such thing as a small two-masted vessel with a mainsail and jib
Sloop rig
special
A ketch or a yawl.
A sloop
schooner
A ketch or a yawl.
catalina capri 14
a dinghy would be a small (6 to 16 foot) sailboat, these can have almost any sail rig. the type of rig you described is called a sloop. a sloop is a sailboat with a triangular mainsail and a jib (this sail configuration is called a marconi rig, or bermudian rig), and are very common. so a small, one masted vessel with a mainsail and jib would just be called a sloop, or dinghy.
The most common single masted sailing vessel with a mainsail and one jib is the sloop.A cutter has one mast with one mainsail but two jibs.A catboat has one mast and a huge mainsail but (usually) no jib. The mast is located very much forward on the vessel.There are other sailboats that have just one mast and a mainsail such as the Sunfish or a Dhow, both of which have a lateen rig (one mast, one mainsail.)
A Jib is a secondary sail which is generaly smaller than the mainsail, and is usually possitioned at the frount of a boat (a foresail). It is generally triangular and is used to counteract the turning force of the mainsail around the pivot point of the vessel in some classes of boat.
Yawls, ketches and two-masted schooners all match this definition. The jib or headsail is not used to define the boat, as almost all fore-and-aft rigged boats have a headsail of some kind.