The most common and most likely answer to this crossword clue is the 8 letter word SCANSION
I've seen this crossword clue in The Times
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More clues leading to the result SCANSION
Buddy explains!

The straight part
We know that "examination of feet" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case examination of feet = scansion.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does SCANSION mean?
SCANSION noun- The rhythm or meter of a line or verse.
- The act of analysing the meter of poetry.
- (of text) Put into a rhythmic form or meter.
- (by extension) Impose patterns on.