Is It a Sin for Catholics to Eat Meat on Fridays?

Must we abstain from meat on Fridays? Simply, no:

          Abstinence from meat, or from some other food as determined by the Episcopal Conference, is to be observed on all Fridays, unless a solemnity should fall on a Friday.                    Abstinence and fasting are to be observed on Ash Wednesday and Good Friday. [Canon MCCLI]

Meat does not have to be abstained from, but abstinence from another food is necessary, otherwise, it is a sin. Although, it is best to abstain from meat for tradition's sake.