harp

1. a musical instrument consisting of a frame supporting a graduated series of parallel strings, played by plucking with the fingers. The modern orchestral harp has an upright frame, with pedals which enable the strings to be retuned to different keys.
2. another term for harmonica.

   Papa had been teaching him to play the blues harp

3. a marine mollusc which has a large vertically ribbed shell with a wide aperture, found chiefly in the Indo-Pacific.

1. talk or write persistently and tediously on (a particular topic).

   I don't want to harp on about the past

   you need to stop harping on her age

2. play on a harp.

   among them harped the divine minstrel Demodocus

Old English hearpe, of Germanic origin; related to Dutch harp and German Harfe .