This is in the spirit of the What is a Word/Phrase™ series started by JLee with a special brand of Phrase™ and Word™ puzzles.
If a word satisfies a certain property, it is called a Ping Pong Word™. Find out what the rule is given the following examples.
| Ping Pong Words™ | Not Ping Pong Words™ |
|---|---|
| DUCK | GOOSE |
| VISUAL | OPTICAL |
| CORNFIELD | PUMPKIN |
| QUANTITY | QUALITY |
| NEIGHBOR | FRIEND |
| WORLD | EARTH |
| TURKEY | CHICKEN |
| EIGHT | NINE |
| ENCHANTMENT | WITCHCRAFT |
