Bolero: a 3/4 dance that originated in Spain in the late 18th century, a combination of the contradanza and the sevillana. It is danced by either a soloist or a couple. It is in a moderately slow tempo and is performed to music which is sung and accompanied by castanets and guitars with lyrics of five to seven syllables in each of four lines per verse. It is in triple time and usually has a triplet on the second beat of each bar.
Barcarolle: a folk song sung by Venetian gondoliers, or a piece of music composed in that style....A barcarolle is characterized by a rhythm reminiscent of the gondolier's stroke, almost invariably a moderate tempo 6/8 meter.