Possible Clues:

• Ocean liner, briefly
• Royally named liner, briefly
• Famed liner, briefly
• Noted liner, briefly
• Helen Mirren's crowning role, informally?
• Retired Cunard liner, briefly
• Retired Cunard flagship, for short
• Ocean liner, familiarly
• Ruler crowned in 1953, informally
• Cunard flagship for 35 yrs.