Not P but Steven Pinker's “Grammar Puss”

[Mike Jing]

>From DFW's "Authority and American Usage":

p. 75–76 “Once introduced, a prescriptive . . .” = Steven Pinker, “Grammar
Puss” (excerpted from ch. 12 of Pinker’s book The Language Instinct,
Morrow, 1994), which appeared in the New Republic on 31 Jan. ’94 (p. 20).
Some of the subsequent Pinker quotations are from the NR excerpt because
they tend to be more compact.

What's the meaning of the title "Grammar Puss"?