Here's a mix of popular and unusual Celtic names for baby boys:

Brendan
From a Welsh word for 'prince.'

Brogan
From the The Irish word bróg, 'shoe,' plus a diminutive suffix.

Cameron (m or f)
From the Scottish words cam, 'bent,' and sròn, 'nose.'

Campbell
From the Scottish words cam, 'bent,' and beul, 'mouth.'

Colwyn
The second element may come from the Welsh word gwen, 'fair, blessed.'

Conan
From the Irish word cú, 'wolf, hound,' plus a diminutive suffix.

Craig
From the Scottish word creag, 'crag.'

Donald
From an early Gaelic name meaning 'world mighty.'

Douglas
From the Gaelic elements dubh, 'dark,' and glas, 'water.'

Duncan
From the Gaelic words donn, 'brown, dark,' and either cath, 'warrior,' or ceann, 'head, chief.'

Dylan
From the Welsh elements dy, perhaps meaning 'great,' and llanw, 'tide.'

Glen
From the Gaelic word gleann, 'mountain valley.'

Gordon
From the Celtic words gor and dun, likely meaning 'great' and 'hill.'

Kennedy (m or f)
One possible origin is the Irish word cinnéidigh, 'helmeted head' or 'ugly head.'

Killian
Irish, either from a word for 'war, strife,' or a different word meaning 'church.'

Lennox
From the Gaelic word leamhann, 'elm,' plus a locational suffix.

Liam
An Irish short form of William.

Logan
Could be from a Scottish place name meaning 'little hollow.'

Maddox
From the Welsh word mad, 'fortunate, good.'

Malcolm
From the Scottish phrase mael coluim, 'disciple of Saint Columba.'

Morgan (m or f)
From the Welsh elements mor and cant, possibly meaning 'sea' and 'circle.'

Nolan
From an Irish name perhaps meaning 'champion' or 'chariot fighter.'

Rhys
From a Welsh word that might mean either 'enthusiasm' or 'ardor.'

Ross
From the Scottish word for 'headland, promontory.'

Ryan
From the Irish word for king, rí, plus a diminutive suffix.

Trevor
From the Welsh words tref, 'town,' and mawr, 'large.'

Vaughan (m or f)
From a Welsh surname meaning 'small, little.'