All individuals of the genera Homo and Australopitecus are considered "hominids." A common trait is bipedality, and tooth morphology is an important diagnostic feature. There are several other recently published generic names, including "Kenyanthropus" (2001), "Ardipithicus" (1994), "Orrorin" (2001), and "Sahelanthropus" (2002). Most of these names are proposed from fragmentary, and in some cases, solitary, specimens. (For instance, I suspect "Kenyanthropus" will be folded into Australopithecus as more fossils are found.)
"Lucy" was, indeed, a hominid. She was not, however, a human.