You might think of a rosy-faced child as a cherub, conjuring up an image of chubby, naked angels cavorting amongst the clouds. That image comes from the most familiar use of the word, which was to name an order of angels.
The image we have of a cherub, chubby-cheeked babies with wings, actually wasn't around until the Renaissance, when artists depicted the lower-order angels as children. Prior to that, the word evolved from the Hebrew kĕrūḇ, and was taken from the Aramaic kĕ-raḇyā which meant "child-like." It was this translation that encouraged the idea of a cherub as being portrayed as a child. The plural form, "cherubim" also follows the Hebrew grammar rule of creating plurals by adding the suffix -im.