grok /grok/, var. /grohk/ [from the novel "Stranger in a Strange Land", by Robert A. Heinlein, where it is a Martian word meaning literally `to drink' and metaphorically `to be one with'] vt. 1. To understand, usually in a global sense. Connotes intimate and exhaustive knowledge. Contrast zen, which is similar supernal understanding experienced as a single brief flash. See also glark. 2. Used of programs, may connote merely sufficient understanding. "Almost all C compilers grok the `void' type these days."