Lute can refer generally to any plucked string instrument with a neck
Neck (music)
The neck is the part of certain string instruments that projects from the main body and is the base of the fingerboard, where the fingers are placed to stop the strings at different pitches. Guitars, lutes, the violin family, and the mandolin family are examples of instruments which have necks.The...

 (either fret
A fret is a raised portion on the neck of a stringed instrument, that extends generally across the full width of the neck. On most modern western instruments, frets are metal strips inserted into the fingerboard...

ted or unfretted) and a deep round back, or more specifically to an instrument from the family of European lutes.

The European lute and the modern Near-Eastern oud
The oud is a pear-shaped stringed instrument commonly used in North African and Middle Eastern music. The modern oud and the European lute both descend from a common ancestor via diverging paths...

 both descend from a common ancestor via diverging evolutionary paths. The lute is used in a great variety of instrumental music from the Medieval to the late Baroque
The Baroque is a period and the style that used exaggerated motion and clear, easily interpreted detail to produce drama, tension, exuberance, and grandeur in sculpture, painting, literature, dance, and music...

 eras and was probably the most important instrument for secular music in the Renaissance
The Renaissance was a cultural movement that spanned roughly the 14th to the 17th century, beginning in Italy in the Late Middle Ages and later spreading to the rest of Europe. The term is also used more loosely to refer to the historical era, but since the changes of the Renaissance were not...