Possible Clues:

• Metrical foot consisting of an unstressed and a stressed syllable
• Metrical foot, in poetry
• Poet's metrical foot
• Foot with first sign of infection attended by a doctor
• da-DAH
• Poetic unit of rhythm
• Foot at first intact needs a doctor
• Foot injury initially seen by a GP, perhaps
• One of three in "To be or not to be"
• 'Macbeth,' but not 'Hamlet'