Definitions in relation to their use in these kangaroo words, taken from Google Dictionary, and edited for formatting.
Kangaroo word: communicative
Joey word: mute
communicative (adjective): ready to talk or impart information.
mute (adjective): refraining from speech or temporarily speechless.
The letters M, U, T, and E found within the anti-kangaroo word “communicative” arrange in the listed order to complete the joey word “mute”. While a word can have multiple definitions, in relation to their use with kangaroo words, these two words share an opposite meaning: speak vs. speechless.