A mobile phone that is built into a wristwatch.(noun)
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Use "wristphone" in a sentence
""You were right," Ordaz told me over the wristphone."
"Will people be rifling through their MP3 collections in 10 years time, happen upon the Ashes win file and replay those golden moments on their new IPod wristphone/video projector/media center?"
"Another figure bustled up, a wristphone pressed to his ear."