Pair periodically entertained by Darling Dicky? (10)
I believe the answer is:
precarious
'dicky?' is the definition.
(both can mean unreliable or unsteady)
'pair periodically entertained by darling' is the wordplay.
'periodically' indicates alternate letters (letters must be selected 'every so often').
'entertained by' indicates putting letters inside (inserted letters are hosted or entertained).
'darling' becomes 'precious' (I am not sure about this - if you are sure you should believe this answer much more).
The alternating letters of 'pair' are 'ar'.
'ar' inserted into 'precious' is 'PRECARIOUS'.
Can you help me to learn more?
(Other definitions for precarious that I've seen before include "Not having a steady position" , "Hairy" , "having difficulty remaining upright" , "Highly insecure" , "Uncertain; likely to fall" .)