From Greek Eustachios meaning fruitful or productive, used as a unisex name.
Stacey is a name that has quietly shapeshifted across gender, origin, and era. It began as a medieval diminutive of two quite different names: Anastasia, the Greek name meaning 'resurrection,' which was borne by a popular early Christian martyr, and Eustace, from the Greek Eustachios meaning 'fruitful' or 'steadfast.' Both roots fed into the shortened colloquial form Stace or Stacy, which appeared in England from the 12th century onward primarily as a masculine pet name and surname.
For several centuries the name lived quietly in surname form — appearing in records across England and Ireland — before re-emerging as a given name in the 20th century. In mid-century America and Britain it pivoted decisively toward women, buoyed by the postwar appetite for soft, friendly names that felt modern without being invented. The spelling variants Stacey and Stacy coexist comfortably, with Stacey more common in Britain and Stacy in the United States.
Popular culture has layered the name with associations ranging from the cheerful girl-next-door of 1970s sitcoms to more complex portrayals in later decades. The Fountains of Wayne song 'Stacy's Mom' (2003) gave the name an ironic pop-culture monument that the name's bearers have navigated with varying degrees of amusement. Today Stacey feels warmly retro — one of those names that peaked in the 1970s and 80s and now carries the pleasant nostalgia of a generation coming into full adulthood.