This is not so much an attempt to provide a different definition than any offered so far, but rather to amalgamate them.
Roughly speaking non-denominational churches:
- Are generally either ecumenical, or in the very least universal in their idea of 'the church'
- Place a greater emphasis on a direct/experiential incarnation of Christianity, rather than an abstracted/formalised description of it.
- Tend to shy away from expressing any explicit form of ecclesiology
- Tend to reject the notion of specifically 'ordained' leaders, favouring a 'priesthood of all believers' approach, but generally still have the person(s) at the front, leading the show.
- Aspire to be more like the early church, and reject the idea that Christians should be divided by anything as arbitrary as theological beliefs.(which Ironically, is a pretty good description of the early Church)
- Tend to have an extremely low view of sacramentology, rejecting all but perhaps the ones Jesus instigated, i.e. 'baptism', 'the Lord's Supper', possibly even 'foot washing' (which to be fair pretty much no-one bothers with, unless some preacher randomly decides to include it as a practical session in their sermon about 'serving one another')
- have no formal statement of belief - but would still generally say they ascribe to the Nicean Creed to avoid being called a cult (unless they actually are a cult, in which case you might as well ignore everything I have said so far and just accept that they are the only valid expression of the church, and you are currently decieved)
- have no overarching governmental body.
- have a "what we believe" section on their website and might even pay subscription fees to the Evangelical Alliance, so that no-one thinks they are a cult.
- have emerged from either a charismatic individual or a dynamic movement, and either die out within the first 30-50 years of their existence, or else go through a phase of formalising their ecclesiology, sacramentology, and soteriology, to the point that they effectively become a denomination of their own. (this could be used to describe the emergence of Christianity itself, as a Jewish sect)
I consider myself a non-denominational Christian (i.e. i tick 'Christian' rather than 'Methodist' on forms), although I currently attend a mainstream denominational church (and really I'm just a 'born again' ex-Catholic, whatever that means)
Clear as mud