I am trying to find a phrase to replace 'longest-serving'. It is in regards to a customer who is the customer who has come to a store for the longest amount of time so they are not really 'serving' more like 'longest-attending' but obviously this does not sound very nice, something along those lines. Any ideas? THANKS
The term long-standing means
Having existed or continued for a long time: a long-standing tradition
Oxford Dictionaries Online
You could say most long-standing customer.
Perhaps you might also say longest-standing customer, but long-standing is a fairly fixed term, and that neologistic phrase might conjure up images of someone waiting in line for the most extended period.
P.S. I wouldn't use this term if you are in the seating business.
I think you could use the expression loyal customer
- (noun [U] UK US Commerce-Marketing)
- the fact of a customer buying products or services from the same company over a long period of time:
(Cambridge Business English Dictionary)