Far too much elastic and gold stitching (2,7)
I believe the answer is:
ad nauseam
'far too much elastic and gold stitching' is the definition.
I can't tell whether this definition defines the answer.
'elastic and gold stitching' is the wordplay.
'elastic' indicates an anagram (the anagram stretches or twists into a new form).
'gold' becomes 'Au' (Au is the chemical symbol for gold).
'stitching' becomes 'seam' (I can't explain this - if you can you should believe this answer much more).
'and' anagrammed gives 'adn'.
'adn'+'au'+'seam'='AD NAUSEAM'
Can you help me to learn more?
(Other definitions for ad nauseam that I've seen before include "Done so often that it becomes tiresome" , "to a sickening degree" , "To a very tiresome degree" , "to an excessive extent" , "To a sickening extent - from Latin" .)