There’s a common acronym for “order of operations” in math that is PEMDAS. Parentheses, Exponents, Multiplication, Division, Addition, Subtraction.

Someone said “order of operations” and another person made a pun with the acronym.

TBH it took me a minute to figure it out, and I literally only found it when I searched for ‘pem da’ and felt like an idiot.

I wasn’t taught the acronym, so it was meaningless to me as well. The acronym actually seems more complicated to me.