Ruby
A surname with more than one possible origin, including a traditional English nickname form and a later Jewish name linked to the gemstone ruby.
The #3,904 most common surname in the United States (2010 Census) — about 1 in every 33,962 Americans shares it.
Etymology
The surname Ruby is not straightforwardly explained by one single source. Some 19th-century surname writers treated it as a form of older English surnames such as Roby, Robie, or Robb, ultimately from the personal name Robert; others suggested a local or place-name origin. In Jewish and German contexts, related forms like Rubinstein clearly point to the ruby gemstone, from words meaning "red" and "ruby."
History
In English records, Ruby appears as a relatively uncommon surname and has been linked by different writers to several older name families, so its history is mixed and sometimes uncertain. In Jewish usage, Ruby and especially related surnames such as Rubin and Rubinstein were adopted or adapted from gemstone-based names, often in the 18th–19th centuries. The modern surname can therefore reflect different independent origins depending on family line.
Origin
Regions
Variant spellings
Fun fact
One old surname dictionary explicitly says Ruby may be “the same as” a whole cluster of Robert-derived surnames, showing how slippery surname spelling could be in earlier records.
From the historical record
“and Yorkshire. RUBY. Probably local ; see termination BY. RUDD. Probably tlie same as Rodd. RUDDER. A corruption of Rutter. RUDDERFORTH. See Rutherfurd. RUDDIFORD. See Rutherfurd.”
— Patronymica Britannica: a dictionary of the family names of the United Kingdom