Sentence:  ‘These speakers are academics who have specialised in Islamic sciences and are well respected in scholarly circles. It is grossly unjust to suggest that they belong to some fringe ideology rather than <WSD>orthodox</WSD> Islam.' 
Meaning of the word marked with <WSD> tags:  Conforming to the accepted, established, or traditional doctrines of a given faith, religion, or ideology. (from 15th c.)