Offside
It was grandma who explained to me what an offside was. She learned to enjoy football from grandpa in the — otherwise grey, but golden for football — 1970s. 20 years later it was time to pass the passion to the, still personality-less, granddaughter.
Watching FIFA on a 21 inch TV I learned it was essential to root for a chosen team, and refer to “the others” with a mild nationally-stereotyping slur.
Grandma would support anyone playing against the Germans or “the Ruskis”. If I went against her, she’d keep a straight face, but her eyes said “traitor”.