Related Clues:

• Not at all excited
• In the 50's or 60's, say
• Stiff-upper-lip type
• Zeno was one
• Long-suffering
• Stone-faced
• Chilly
• Awesome
• Hard to move
• 'Groovy!'
• Indifferent
• Unfeeling
• Yachter's woe
• Calm and collected
• 'Rad!'