We know exactly what someone means when they say "bubblegum flavor," because we've tried bubblegum. But if you were to describe that flavor in terms of flavors found in nature, you might be stumped. What flavors go into bubblegum to make it taste that way? The best I could decipher from an article at Spoon University is that it's like "tutti-fruiti."
Bubble gum flavor is one of the secrets of the gum industry, with a cocktail of artificial fruity flavors at the center of it. Homemade versions tend to utilize the more easily available strawberry flavor, but true bubble gum flavor is more complex, composed of multiple notes.
I never thought of fruit when chewing bubblegum, but there it is. You'll find even more information in the discussion thread at Metafilter.
(Image credit: Mary (Mayr))