Hehh-duHpp

Hehh-duHpp is a Klingon exercise used to teach infants hand-eye coordination so they can grow up to become warriors. It involves shaking a rattle in front of them to teach them rhythm and hand-eye coordination.

While taking care of the infant Kirayoshi O'Brien, Worf tried to teach him some hehh-duHpp. Later, he was inordinately pleased to hear from his wife, Jadzia Dax, that Yoshi had been repeating the ritual phrase to himself. 

Lyrics:
 * wa-TacH,
 * ''doo-Ga-ya,
 * gung-gung-gung.