Meaning

1. key (to open doors)
2. key (of musical instrument)
3. key (crucial step)
4. wrench, spanner
5. curly bracket
6. faucet, tap, water tap, spigot
7. switch (a device to turn electric current on and off or direct its flow)
8. hold (position or grip used to control the opponent)
9. a local sport or game
10. type of knot