Mullin
Usually an Irish surname from Gaelic forms meaning “descendant of Maolán,” though in some cases it may also reflect French names for a miller or a mill.
The #3,250 most common surname in the United States (2010 Census) — about 1 in every 27,807 Americans shares it.
Etymology
The strongest Irish explanation connects Mullin with Gaelic O’Maoláin, meaning “descendant of Maolán,” a personal name built on maol, “bald” or “tonsured,” often found in early Irish names. Historical surname writers also note a French line of explanation from Du Moulin, literally “of the mill,” from French moulin and Latin molina/molinus, referring to a mill or to someone living by or working at one. Because both forms existed, the surname can have different origins in different families.
History
In Irish records, variants such as O’Mullin, Mullen, Mullen, Moylan, and related spellings are grouped with the Gaelic O’Maoláin family name in older sources. English and French bearers could also have adopted or anglicized forms from Du Moulin or similar occupational/topographic names. The surname is well attested in Ireland and among Irish emigrant communities, but it is not always possible to tell from spelling alone which origin a particular family has.
Origin
Regions
Variant spellings
Fun fact
Old surname dictionaries sometimes treated Mullin as belonging to more than one family line at once, which is why the same spelling can have both Gaelic and French explanations.
From the historical record
“Maolagdn,Maolacdn:v.lA\\\\ga.n,M\\\\ca.n\ MULLIN (Celt.) for the Irish O'Maoldin = Descendant of M aolan [v. M u 1 1 an ' ] (A.-Fr.-Lat.) for the common French (Du) Moulin = (Of the) Mill [Fr. moulin, L.Lat. molin-us, f. Lat. mola, a mill] Mulliner”
— Surnames of the United Kingdom: a concise etymological dictionary (2 vols in 1)