What does 'Secular' mean?

Correspondence in this week's 'Tablet' suggests a need to clarify the meaning of 'secular'. Is it about religious *institutions* (i.e. secular = independent of any religious institution) or about belief (i.e. secular = not believing in God)?

When I opposed so-called 'faith schools' in a debate organised by the British Humanist Association it was as a religious believer convinced that education needed to happen in a space that is not controlled by any religious institution. I did so out of (misguided?) Reformed conviction. Indeed, it was my desire to stake out a place for committed religious believers in the secular sphere, rather than assume that 'God' is only 'done' within the confines of religious institutions that prompted me to seize the opportunity when it presented itself. (My speech can be found on the Articles and Sermons page of www.urctemplecowley.org.uk).

In this context, I note that plans for a joint Christian-Muslim 'academy' ("faith school", presumably)in Oldham, proposed by the Anglican diocese, have been shelved by the local authority on the grounds that there is already sufficient provision for pupils of faith in the town. Does this betray confusion over the true meaning of 'secular'?