Grandma horn

refers to the gramophone-like shape of a plastic bag stuck into any vessel (bottles, cartoons or bowls etc.) to funnel or contain/include.

Jack II: In those good old days of wooden dinghies, no guys would hesitate when the nature called you. No cond-u-its, not even T-party kids in ports.
Jackie: But ladies should truely thank Prauda brains, who turned those stinky sailcloth buckets into fashionable wash&dry TOTO bags!
Rose: So, grandma horns wasn't grandma's idea, anyway...