Grok is a word coined by Robert A. Heinlein for his 1961 science-fiction novel, Stranger in a Strange Land, where it is defined as follows:

Grok means to understand so thoroughly that the observer becomes a part of the observed—to merge, blend, intermarry, lose identity in group experience. It means almost everything that we mean by religion, philosophy, and science—and it means as little to us (because of our Earthling assumptions) as color means to a blind man.

The Oxford English Dictionary defines to grok as “to understand intuitively or by empathy; to establish rapport with” and “to empathize or communicate sympathetically (with); also, to experience enjoyment”.

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