From WordNet (r) 3.0 (2006) [wn]:
Lao
adj 1: of or relating to a member of the Buddhist people
inhabiting the Mekong river in Laos and Thailand
n 1: a member of a Buddhist people inhabiting the area of the
Mekong River in Laos and Thailand and speaking the Lao
language; related to the Thais [syn: Lao, Laotian]
2: the Tai language of a Buddhist people living in the area of
the Mekong River in Thailand and Laos