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.
There have been quite a few researchers (paleos and scientists of various disciplines) who have concluded Lucy was an ape. Some have said it was an orangutan. The bottom line is it ain't human.