IRB

Noun

 * , a committee that reviews the designs of proposed experiments to confirm whether all the methods proposed are ethical.
 * , a committee of business executives who review investment choices, comparing against strategy and opportunity costs.
 * , an internal affairs division of a police department.

Adjective

 * 1)   approach

Proper noun

 * 1)   a secret organisation dedicated to the establishment of an "independent democratic republic" in Ireland between 1858 and 1924.
 * 2)   the name used by World Rugby, the worldwide governing body for rugby union, from 1998 to 2014.