“Against the spread” refers to betting on a team to perform better than the point spread set by the sportsbook. They must either win by a margin greater than the spread (for favorites) or lose by fewer points than the spread (for underdogs) for the bet to be successful.
Quote from NY Post Point spreads are supposed to be the great equalizer. History has shown that the eventual champions are often underestimated by the composite sum of market influences, even when they’re media-friendly, high-profile programs. Consistently clearing high expectations is a sign of greatness.
I think there is a difference between “Is this team underestimated in the real NFL game?” That answer is obviously not at all.
and
“Is Vegas underestimating this team by not making the spread larger?” And based on the stats I would say they are.
In NFL games the Eagles are estimated perfectly, but I’m betting the Eagles are underestimated.