Green’s Dictionary of Slang

1. (US/P.R.) a woman, usu. pretty and young; thus tremendos pollos n., a collective term for good-looking (lit. ‘tremendous’) women.

1975

E. Torres Carlito’s Way 18: Tremendos pollos. White, black, tan, green ’n in b’tween.

2. (US) an illegal Mexican immigrant.

1980		in S. Terkel Amer. Dreams (1982) 34: A coyote is a smuggler of people. He’s also called called pollero. Pollo is chicken. He’s the one who guides chickens through the border.
1984		J. Wambaugh Lines and Shadows 89: The tunnel was a popular place for pollos to duck across the line.
2012		M. MacLean ‘Just Like Maria’ in ThugLit Oct. [ebook] ‘She’s not the type to ride in the back of a U-haul with 20 other pollos’.