Dictionary.com
Thesaurus.com

codpiece

American  
[kod-pees] / ˈkɒdˌpis /

noun

  1. (in the 15th and 16th centuries) a flap or cover for the crotch in men's hose or tight-fitting breeches, usually matching the costume and often decorated.

  2. Obsolete. penis.


codpiece British  
/ ˈkɒdˌpiːs /

noun

  1. a bag covering the male genitals, attached to hose or breeches by laces, etc, worn in the 15th and 16th centuries

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of codpiece

1400–50; late Middle English. See cod 2, piece