Doubt there's any that call at Littlehampton as a mid-point save for diversions.So have we established what the most is? Lot of people coming up with two, a few threes but don’t think any fours.
is there any trains that call at Alderington, littlehampton, Warblington, Bedhampton and Southampton?
However you can get on a train at Wolverton that calls at Northampton, Hampton-in-arden and Marston Green. Sadly I think trains that call at Cheddington and Wolverton don't go beyond Northampton so you don't get a 5. When it was splitting/joining at New Street you might have got a couple more in.
In any case, I thought the OP was asking for stations where the entire word was contained, not just an overlapping syllable? E.g. Eltham and New Eltham.