The lead story in the NYT Sunday Review section on the 23rd was headed “One Nation Under God?: A fifth of Americans now list their religious affiliation as ‘none.'” and began
This week millions of “Chreasters” — Americans who attend church only on Christmas and Easter — will crowd into pews to sing carols and renew their vague relationship with the Christian God.
The portmanteau Chreaster isn’t new, although I have no idea of its history, but what makes it more than routine is the connection between its form and meaning.
The crucial fact is that Chreaster refers to a type of person, not to an assemblage of two holidays (as you would expect from its sources). That interpretation is encouraged by the appearance of the -er, which has no function in Easter but is otherwise involved in a variety of derivational formations, some of them referring to types of persons: not only the agentive -er of reader and the like, but also more inventive uses, as in nutter ‘crazy person’ and birther ‘someone who denies that Barack Obama was born in the United States’. So Chreaster is a portmanteau with an extra twist.