Related Clues:

• Letters denoting holder of university doctorate
• Rifts of supreme sort
• Initially a top university degree
• The one that precedes all others, in time say
• Highest university degree
• The doctor will tell you how acid deuterium is
• Trees start to give it a start
• Conifer Street is before you get to 1 across
• 'Tree at the top of the street, perhaps (5)'
• The tree is over the road, but not for a second
• A good defense may result in it, briefly
• Advanced deg
• Blue-ribbon place
• Safety ___
• High deg