XXXX
/ˈfɔːrɛks/(also Fourex, four-X) British informal
noun
Used as a humorously euphemistic substitute for a four-letter swear word (usually ‘fuck’) in not to give a XXXX and variants: not to care at all, not to give a damn.
- The phrase originated in a series of British television advertisements for Castlemaine XXXX lager..
Origin
1980s; earliest use found in The Sunday Times. From the trademark Castlemaine XXXX, a brand of Australian lager, punningly after the use of X to replace an unknown or suppressed name, number, etc.