Mullis
Usually a spelling shaped from Mullins, ultimately from the medieval name Mullin or Mullen.
The #3,954 most common surname in the United States (2010 Census) — about 1 in every 34,294 Americans shares it.
Etymology
The most likely explanation is that Mullis is a variant or altered form of Mullins, as noted in older surname dictionaries. Mullins itself is commonly linked to the medieval personal name Mullen or Mullin, often treated as a pet form of an earlier personal name. The surname may also reflect later spelling variation in English records, where sounds and endings shifted over time.
History
19th-century surname writers treated Mullis as a corruption or variant of Mullins. Because the name appears in English-language records with several close spellings, it likely spread through ordinary record-keeping variation rather than from a single fixed medieval form. In the United States, Mullis is uncommon but established, especially in families descended from earlier British Isles lines.
Origin
Regions
Variant spellings
Fun fact
Older surname literature sometimes grouped Mullis with a cluster of names that changed by small sound shifts, such as Collins becoming Collis.
From the historical record
“Molines. MULLIS. Perhaps a corruption of Mullins, like Collis from Collins. MULLNICKS. A barbarous corruption of Molineux. MULLOY. O'MULLOY. An ancient race, in whom vests hereditarily the honour of Standard-bearer to the King in Ireland — an honour confirmed so lately as the year 1634. The pi-esent head of the…”
— Patronymica Britannica: a dictionary of the family names of the United Kingdom