Possible Clues:

• EEE, for some shoes
• Length x ___ x height
• Length's counterpart
• 'The -- of a Circle', David Bowie song from the album 'The Man Who Sold the World'
• Diameter inside accompanying measurement across
• It goes from side to side?
• Distance displayed by daughter accompanying escorts
• Not length, the other
• Swim this distance, accompanying daughter to centre?
• Shoe store measure