1. devoid of warmth and cordiality; expressive of unfriendliness or disdain
a frigid greeting; got a frosty reception; a frozen look on their faces; a glacial handshake; icy stare; wintry smile;
Synonyms : ['frigid', 'frozen', 'glacial', 'icy', 'wintry']

2. covered with frost; ; -Wm.Faulkner
a frosty glass; hedgerows were rimed and stiff with frost;
Synonyms : ['rimed', 'rimy']

3. pleasantly cold and invigorating
crisp clear nights and frosty mornings; a nipping wind; a nippy fall day; snappy weather;
Synonyms : ['crisp', 'nipping', 'nippy', 'snappy']