Change encountered, moors a ship awkwardly (13)
I believe the answer is:
metamorphosis
'change' is the definition.
(metamorphosis is a kind of change)
'encountered moors a ship awkwardly' is the wordplay.
'encountered' becomes 'met' ('meet' can be a synonym of 'encounter').
'awkwardly' is an anagram indicator.
'moors'+'a'+'ship'='moorsaship'
'moorsaship' is an anagram of 'amorphosis'.
'met'+'amorphosis'='METAMORPHOSIS'
(Other definitions for metamorphosis that I've seen before include "Transmutation" , "Complete change of appearance" , "Total change in form" , "Process of transformation" , "changing?" .)