Poor satire upset one, from experience (1,10)
I believe the answer is:
a posteriori
'from experience' is the definition.
(relating to knowledge learned from experience)
'poor satire upset one' is the wordplay.
'upset' indicates anagramming the letters.
'one' becomes 'i' (Roman numeral).
'poor'+'satire'='poorsatire'
'poorsatire' with letters rearranged gives 'aposterior'.
'aposterior'+'i'='A POSTERIORI'
(Other definitions for a posteriori that I've seen before include "based on experience" , "judging by experience?" , "using evidence" , "affected by experience" , "empiricism" .)