Etymology of Viagra

[Douglas G. Wilson]

Without having any specific knowledge, I would speculate that "Viagra" is
intended to be reminiscent of "vigor". Actually I'm sure it is a nonsense
coinage primarily designed to avoid stepping on anybody else's trademark. I
doubt the company will admit to ANY intentional meaning or connotation ...
somebody might sue because he didn't get 'vigorous' or whatever.

-- Doug Wilson