flatten

verb9

1. •
   To make something flat or flatter.

   • As there was a lot of damage, we chose the heavy roller to flatten the pitch.
   • Mary would flatten the dough before rolling it into pretzels.
2. •
   To become flat or flatter; to plateau.

   • Prices have flattened out.
3. •
   To knock down or lay low.

   • The prize fighter quickly flattened his challenger.
4. •
   To be knocked down or laid low.
5. •
   [with oneself] To press one's body tightly against a surface, such as a wall or floor, especially in order to avoid being seen or harmed.
6. •
   To reduce (a data structure) to one that has fewer dimensions, e.g. a 2×2 array into a list of four elements.
7. •
   To combine (separate layers) into a single image.
8. •
   To make vapid or insipid; to render stale.
9. •
   To lower by a semitone.