Act 2:42 And they continued stedfastly in the apostles' doctrine and fellowship, and in breaking of bread, and in prayers.
Sometimes people ask "Where do you fellowship?" Also they ask "Who do you fellowship with?" But it would be a rare thing for someone to ask "What is your fellowship for?"
An unbeliever might ask "What do you do at your meetings?", not knowing how the term "fellowship" is applied among Christians.
I sometimes mention who I am in fellowship with and comment on what matters we discuss, and occasionally describe someone as being "out of fellowship", but still the question remains, "Ideally As Christians What Is Our Fellowship For?"