A Kirk is just another word for a church, normally a Scottish church (:
Kirk Hinrich goes by Captain Kirk.
Kirk Hammett goes by The Ripper, and Kirk Hampster.
LEGOs were created by Ole Kirk Christiansen and his son Godtfred Kirk Christansen.
McCoy called Kirk "Jim". Kirk called McCoy "Bones"
Kirk Krogstad's birth name is Kirk Anthony Krogstad.
Kirk Lowdermilk's birth name is Robert Kirk Lowdermilk.
Kirk Rueter's birth name is Kirk Wesley Rueter.
Keith Kirk's birth name is Keith Byron Kirk.
Terence Kirk's birth name is Terence Sumner Kirk.
Tommy Kirk's birth name is Thomas Harvey Kirk.
Kirk Honeycutt's birth name is Kirk Russell Honeycutt.
Kirk Dwyer's birth name is Kirk Lee Dwyer.