Definition of bikeshed:
(n) :
(literally) An enclosed structure where bicycles may be stored.
(n) :
(figuratively, chiefly software engineering) A topic that is attracting debate out of proportion to its actual importance.
(v) :
(chiefly software engineering) To discuss a minor detail rather than focusing on more important issues.
(n) :
(transportation planning, urban studies) The land area within a defined biking range of a specified location.