An interesting quote from Robert Hatten’s 2004 book on musical gestures:
Musical gesture is biologically and culturally grounded in communicative human movement. Gesture draws upon the close interaction (and intermodality) of a range of human perceptual and motor systems to synthesize the energetic shaping of motion through time into significant events with unique expressive force. The biological and cultural motivations of musical gesture are further negotiated within the conventions of a musical style, whose elements include both the discrete (pitch, rhythm, meter) and the analog (dynamics, articulation, temporal pacing). Musical gestures are emergent gestalts that convey affective motion, emotion, and agency by fusing otherwise separate elements into continuities of shape and force.
Thus for him, musical gesture is an inner-musical quality, funded in biology and culture.