::Terms can be applied retrospectively and often are, feminist being an example (it's applied to Mary Wollstonecraft although the word is attested for a dictionary only later). It is appropriate to label the usage as retrospective, if desired. 

 ::If the article is adequately sourced but the term atheist feminism is not, given that terms such as Jewish feminism and Christian feminism are established, then an alternative term should be proposed and then, if the article is moved, the presumed redirect from atheist feminism preserved. 

 ::I'm not judging the article as a whole. 

 ::