The core fast day. We abstain from meat and poultry, from fish (that is, fish with a backbone), from dairy and eggs, and from wine and oil. Shellfish, and foods without animal products, are kept.
This is the strict weekday pattern of the great fasts. On ordinary Wednesdays and Fridays through the year the same abstinence is kept, though in many places wine and oil are allowed on those days · practice varies, and this is exactly the kind of thing to settle with your priest.