HolQeD 12:4, p. 8: "Maltz's Reward: Part III." 

The head has a number of organs through which substances enter and exit the body, and there is vocabulary for the bodily functions involved in this movement of substances. Air, for example, comes in and out of the nose or mouth. The word for "breath" is tlhuH, and that for "breathe" is also tlhuH. To breathe in, or "inhale," is pur; to breathe out, or "exhale," is rech. To breathe noisily, or "wheeze," is jev. (This is also the verb "storm," though Maltz couldn't decide whether this was meaningful or just a coincidence.) To breathe even more noisily, or "snore," is wuD.

When air (or gas) from the stomach works it's way up and comes out of the mouth (often noisily), one is said to ruq "belch." Maltz said it is acceptable to refer to this gas as SIp, a general word for gas of any kind, but that gas produced within the body is known as Qep'It. When, rather than gas, undigested or partially digested food comes up, one is said to 'em "vomit," and the matter being vomited, that is, "vomit," is called quy'Ip. (Maltz was quite amused whet he realized that Klingon word rech "exhale" sounded like the English word "retch" -- that is, "vomit" -- but he couldn't explain why he thought it was so funny.) The verb for "hiccup" is bur. The verb meaning "gurgle," specifically applied to one's stomach gurgling or talking, is bor.