Kelly
KEL-ee
A name with Gaelic roots, long associated with bright-haired or lively Irish and Scottish surname traditions.
Meaning
Kelly is most commonly traced to an Irish Gaelic surname, usually linked to the older name Ó Ceallaigh. In traditional etymology, this is often explained as referring to a descendant of Ceallach, a name associated with meanings such as "war" or "strife," though the name also became widespread as a surname and later a given name. The excerpted source also shows it being discussed in a Gaelic surname context, but it does not give a full derivation in the visible text.
Origin
Irish GaelicScottish Gaelicunisex
Fun fact
Kelly became one of those surnames that later crossed over into common use as a first name, especially in English-speaking countries.
Confidence: mixed. Sources: History of Christian Names.