Dealing with a period of illness (5)
I believe the answer is:
about
'dealing with a period of illness' is the definition.
I can't judge whether this definition defines the answer.
'with a period of illness' is the wordplay.
'with' means one lot of letters go next to another.
'period of illness' becomes 'bout' (as in a bout of flu).
'a' next to 'bout' is 'ABOUT'.
Can you help me to learn more?
(Other definitions for about that I've seen before include "not far away" , "Concerning (something)" , "Almost; around" , "Regarding" , "Moving" .)