Bitcoin (BTC).
Am pretty sure it was Satoshi himself. There's a passage in Digital Gold by Nathaniel Popper where it's proposed in an exchange with that Finnish fella who helped him out with bitcoin.org at the start. I'll dig around.
Edit - It was an unknown stranger.
'While satoshi never discussed anything person in these emails, he would banter with Martti about little things.
In one email Satoshi pointed to a recent exchange on the Bitcoin email list in which a user referred to Bitcoin as a "cryptocurrency" referring to the cryptographic functions that made it run.
"Maybe it's a word we should use when describing Bitcoin. Do you like it?" Satoshi asked.
"It sounds good," Martti replied. "A peer to peer cryptocurrency could be the slogan." '
BitcoinFX - Date Registered: February 01, 2010, 04:59:51 PM
Jan 2010 ... 1st Snapshot Reference for bitcoin.org ...
"Bitcoin P2P Cryptocurrency" <<<<<
does pre-date my OP post !!!-
https://web.archive.org/web/20100106082749/http://www.bitcoin.org/...snip...
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