Fast gallop running at rear of stable is bound to raise standards (8)
I believe the answer is:
Here is my best explanation:
'bound to raise standards' is the definition.
I can't judge whether this defines the answer.
'fast gallop running at rear of stable' is the subsidiary indication.
'fast' becomes 'f' (this could be a standard abbreviation I've not previously seen).
'running' indicates anagramming the letters.
'at' means one lot of letters go next to another.
'rear of' says to take the final letters.
The final letter of 'stable' is 'e'.
'gallop' is an anagram of 'lagpol'.
'is' is the link.
(Other definitions for flagpole that I've seen before include "Mast on which banner is hoist", "Pin", "means to raise standard", "Support for banner.", "Ceremonial mast", "Standard post", "upholder", "On which standard flies", "Upholder of standards" and "standard-bearer".)