Person with two jobs: second one mostly easier (11)
I believe the answer is:
moonlighter
'person with two jobs' is the definition.
I don't know anything about this answer so I can't tell whether this works.
'second one mostly easier' is the wordplay.
'second' becomes 'mo' (both are short periods of time).
'mostly' means to remove the last letter (most but not all of the word).
'easier' becomes 'lighter' ('light' can be similar in meaning to 'easy').
'one' with its last letter taken away is 'on'.
'mo'+'on'+'lighter'='MOONLIGHTER'
Can you help me to learn more?
(Other definitions for moonlighter that I've seen before include "he performs more than one job" , "Person with more than one job" , "someone who's got an extra job" , "One holding another job" , "one taking extra work" .)