gua·cha·ro or guá·cha·ro 
(gwächə-rō′)
(gwächə-rō′)n. pl. gua·cha·ros or guá·cha·ros
A nightjar (Steatornis caripensis) of northern South America that roosts in caves and eats fruit. The young birds were formerly collected for their fat, which was used for cooking oil. Also called oilbird.
[American Spanish guácharo, from guacho, vagabond, from Quechua wakcha, wahcha, poor person, orphan (the bird perhaps being so called because of its plaintive cries).]