Japanese

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For pronunciation and definitions of ちゃっきょ – see the following entry.
着拒
[noun] (informal) Short for 着信拒否 (chakushin kyohi, rejecting a call).
[verb] (informal) Short for 着信拒否する (chakushin kyohi suru, to reject a call).
(This term, ちゃっきょ (chakkyo), is the hiragana spelling of the above term.)