What is a Ping Pong Word™?

Question

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

phenomist · Accepted Answer

A Ping Pong Word™ is a word that

One Answer