Definition of "backslash"
(computing, rare, proscribed) Used erroneously in reference to, or in reading out, the ordinary slash, that is, the punctuation mark /.
Quotations
Also, avoid submenus[sic] that can confuse the audience—if you're giving lengthy Web site addresses full of backslashes, shorten it so only the Web site's home page is given.
2010, Frank Barnas, Ted White, Broadcast News Writing, Reporting, and Producing, Fifth Edition, Elsevier, page 114
verb
third-person singular simple present backslashes, present participle backslashing, simple past and past participle backslashed