green top noun4 •(UK) Milk of the kind sold with a green top, or a bottle thereof. •(UK) Semi-skimmed milkRed top milk is in and green top milk is out, according to Guernsey Dairy, which has seen sales of full fat milk increase by 30% since 2019. — 2026 •(UK, Wales) Unpasteurized full-cream milk.Green-top (untreated raw retail liquid milk) production is closely monitored by on-farm checks. — 1989 •A pitch with abundant visible grass. formsgreen tops