gua·ya·ber·a 
(gwī′ə-bĕrə)
(gwī′ə-bĕrə)n.
A light, collared, usually short-sleeved shirt having buttons and pleats down the front and often large pockets, and typically worn outside the pants.
[American Spanish, perhaps from Spanish guayaba, guava (from the fact that the pockets are suitable for holding guavas); see GUAVA, or alteration of (camisa) yayabera, (shirt) in the Yayabo River style (after the Yayabo River in central Cuba).]