Connelly
An Irish surname from Mac Conghalaigh, meaning “son of Conghalach,” a personal name associated with conflict or valor.
The #1,537 most common surname in the United States (2010 Census) — about 1 in every 13,195 Americans shares it.
Etymology
Connelly is generally an Anglicized form of the Irish Mac Conghalaigh. The personal name Conghalach is usually explained from congall or congalar-related elements connected with strife, conflict, or heroic action, so the surname originally meant “son of Conghalach” rather than a direct descriptive term. Older writers sometimes offered looser Gaelic explanations, but the Irish patronymic derivation is the standard one.
History
The name is especially associated with Ireland, where it appears in several counties and was recorded in both Connacht and Ulster as well as other regions. In English-language records it often appears beside related forms such as Connolly, O'Connell, Kennelly, and Conneely, reflecting the fluid spelling of Irish surnames under anglicization. In some cases, Connelly may reflect local spelling preferences or variants of the same underlying Irish family name.
Origin
Regions
Variant spellings
Fun fact
A 19th-century Manx source explicitly notes Connelly as a shortened form of Mac Conghalaigh, showing how Irish surnames could be reshaped in island communities outside Ireland itself.
From the historical record
“head of the valley. CONNELL or CONNELLY. (Celtic and Gaelic.) From conal, love, friendship. CONNOR or CONOE. (Celtic and Gaelic.) From Conchobar, the chief of men, powerful among men, a leader. O'Dono- van derives this name from Conn, strength, and colhair, aid,”
— An Etymological Dictionary of Family and Christian Names