What are you talking about? The literal difference between a herb and a tree is the presence of wood. This isn’t referring to the culinary term for herb, it’s referring to the short version of the botanical term “herbaceous”, which are plants that aren’t lignified, aka they don’t have a woody stem like trees or shrubs do. The terms absolutely do have scientific meaning. Banana plants do not have woody stems, hence they are herbs, aka herbaceous plants. In general terms we call them trees, but in a botanical sense they aren’t the same thing.