Mike,

Short answer: a path or lane.

Long answer (which you didn't ask for, but it's a neat scenic tour):

Ancient Ireland was a pastoral culture. Life, livelihood, law, and a certain chunk of the language, revolved around the cow (bó).

To this day, bóthar is the generic Irish word for "road". It is a worn-down version of the phrase bó thar bhó ("cow passing cow," which was considered the proper width for a road to be.)

Bóithrín is simply the diminutive form of bóthar.

;)

Slán,

~Fionn

www.geocities.com/children_of_lir