Rheagan is a spelling variant of Reagan, from an Irish surname meaning 'little king.'
Rheagan is a creative respelling of Reagan (also Regan), an Irish surname turned given name with roots in the Gaelic family name Ó Riagáin — "descendant of Riagán." The personal name Riagán is thought to derive from the Old Irish *rí* (king) combined with a diminutive suffix, yielding something close to "little king" or "the kingly one." It was a notable family name in medieval Munster and Connacht, and the Ó Riagáin clan held lands in counties Tipperary and Meath before the upheavals of the Norman conquest reshuffled the Irish aristocracy.
In the English literary tradition, Regan carries a darker shade: she is one of King Lear's treacherous daughters in Shakespeare's tragedy, a character of cold calculation and cruelty. That association has not significantly burdened the name in practice, perhaps because most modern parents encounter it through entirely different channels — primarily through President Ronald Reagan, whose two terms in the 1980s made the surname familiar and, to his admirers, resonant with a particular American optimism. After Reagan's presidency, both Reagan and its variants began a long climb as given names, particularly in the United States.
The Rheagan spelling, with its distinctive *rh* opening borrowed loosely from Welsh phonetics (where *rh* signals a voiceless trill) and its *-agan* ending, gives the name a slightly more Celtic, antiquarian appearance on the page. It appeals to parents who want something identifiably Irish in heritage but with a spelling that signals they have thought carefully about individuality. It is a name that wears its origins lightly while feeling entirely of its own moment.