Usually written ol' chap since the apostrophe should be placed where the missing letter is. Short form for "Old Chap", which is a British way of saying "Dude".
"My word, 'ol chap, the Queen just snogged that fag." means "Check it out, dude, the Queen just french kissed that cigarette."
by SeanAnthonySmith March 24, 2006
by *princess* September 08, 2005