against the spread in nhl,what does it mean?

[tbird509]

now this may be a stupid question,but what does against the spread mean in hockey,im guessing it means the puck line,can anybody help me out...im not talking about the favs/underdogs straight up,i need to find answer out asap,once somebody gives answer,ill explain why,and this info could be worth some good money

[nyplayer33]

example..tues eve..the sharks are minus 1.5 goals on the puck line vs buffalo...if you take the sharks they must win by 2 goals or more