the.com/cardinal sin
Not a bird crime — the one mistake so basic it ends the argument before it starts.
means A fundamental, foundational error — a mistake in the most basic rule of something, serious enough to invalidate everything built on top of it.
from From Catholic theology's 'cardinal sins,' the gravest moral failings, with 'cardinal' meaning 'hinge' — from Latin cardo, the pivot a door swings on. These were the sins everything else turned on, the hinge-point faults. The word traveled the same path into 'cardinal virtues' and 'cardinal numbers': the core thing other things hinge upon. The cardinal bird and cardinal(ity) in church rank share that root too, named for the 'principal' or 'chief' sense of the word, not because any of them involve actual birds.
- origin
- from Latin cardo, the hinge everything else turns on
- not biblical
- the actual seven deadly sins have their own list
- usage today
- means an unforgivable, rookie-level screwup
- classic example
- telling a chef their sauce needs ketchup