The guitar as an instrument, as well as the name 'guitar' are ultimately derived from the
Ancient Greek 'Kitarra,' which was a sort of
lyre. This word eventually passed into
Arabic as 'Quitar' and likely described a range of stringed
instruments such as
udes. In the
middle ages, the people of the
Iberian Peninsula adopted this word from their
Moorish rulers, and it was applied to the stringed instrument being developed and played by the local
gypsies and others. The word became 'guitarra' in
Spanish and the English word 'guitar' is a borrowing from that. So we have the rather unique situation of an English word being descended from Ancient
Greek but not through
Latin or
Rennaissance era scientific borrowing, but through Arabic.
However the acoustic guitar as we know it today did not assume its present form in terms of appearance, sound, and tuning until possibly as late as the 19th century. This is an amazingly recent pedigree for an instrument that has so dominated and defined many of the popular forms of music worldwide in the past 50 years.