Pecking into Inherent Vice

[Mark Kohut]

p. 2..."Gentleman of the straightworld persuasion", he [Doc] beamed.

Anybody else surprised by this sentence? Anyone have access to an OED?
Was straightworld a single word in 1970?  I only know it---and Googling
it--- only leads to two words, "straight world"......Printing mistake?
Neologism?

What is he asking? Not about the guy's sexual orientation, we know. Straight meaning establishment? vs. their counter-culture world?  

Online, nother scientific meaning:
We define a straight world line as the history of an unaccelerated par- ticle. In spacetime diagrams such world lines will also be drawn as straight lines. ...

Related to flatland in IV? You Californians of an age (or who know history
better'n me). Was that word used in California then the way it is in IV? This flatlander never heard it.