The alphabet.
"The medical team immediately initiated ABCs to stabilize the trauma patient's vital functions."
Initialism of airway, breathing and circulation: the essential steps in the immediate assessment and treatment of critically ill or injured patients.
In plain English: Abc is the first three letters of the alphabet that kids learn to read and write.
"She was struggling with the basics, so she had to memorize her ABCs again before starting to read."
Usage: In medical contexts, ABCs refer to the critical first steps of assessing airway, breathing, and circulation in emergency situations. Outside of medicine, the term simply denotes the first three letters of the English alphabet used for teaching children how to read and write.
Initialism of atomic, biological and chemical: the three main categories of weapons of mass destruction.
"The treaty specifically banned all forms of abc weaponry to prevent future global catastrophes."
In plain English: Something that is abc is very basic, easy to do, or requires little effort.
"The analyst warned that an abc threat required a multifaceted response strategy."
Usage: Do not use "ABC" as an adjective to describe weapons of mass destruction in casual conversation, as this technical military term is rarely understood by the general public. In everyday usage, people typically refer to these weapons simply as nuclear, biological, and chemical weapons rather than using the acronym ABC.
Initialism of American Broadcasting Company: an American commercial broadcast television network founded in 1943.
"Many classic sitcoms from the 1950s are still available to stream on ABC today."
Initialism of anything but Chardonnay: a backlash against Chardonnay wine, seen as ubiquitous.
"The sommelier's decision to serve an obscure red instead of the overused white was a clear act of abc in response to the region's chardonnay glut."
The word comes from Middle English abece, which referred to the first three letters of the Latin alphabet. It was used as a shorthand to represent the entire alphabet.