arcar

A rare, largely dialectal verb functioning as a synonym of arquear — to arch or curve something, or, in music, to bow a stringed instrument. Most Spanish speakers today would default to arquear rather than arcar.

• El violinista arcó las cuerdas con suavidad. — The violinist bowed the strings gently.
• La madera se arcó con la humedad. — The wood arched/warped with the humidity.
• Arcaron la estructura para darle una curva elegante. — They arched the structure to give it an elegant curve.

Using arcar expecting it to be widely recognized — arquear is the standard, much more common verb for the same meanings (arching, bowing an instrument, or gauging a ship's tonnage); arcar will sound obscure or regional to most listeners.

Often confused with arquear.