The standard four food groups are based on American agricultural lobbies. Why do we have a milk group? Because we have a National Dairy Council. Why do we have a meat group? Because we have an extremely powerful meat lobby.
A figure of speech in which words are used to imitate sounds. Examples of onomatopoeic words are buzz, hiss, zing, clippety-clop, and tick-tock. Keats's "Ode to a Nightingale" not only uses onomatopoeia, but calls our attention to it: