Academic point about frost-covered lake (7)
I believe the answer is:
scholar
'academic' is the definition.
(I've seen this before)
'point about frost-covered lake' is the wordplay.
'point about' becomes 'sc' (I can't justify this - if you can you should believe this answer much more).
'frost' becomes 'hoar' (synonyms).
'covered' means one lot of letters goes inside another.
'lake' becomes 'L' (geographical abbreviation).
'hoar' going around 'l' is 'holar'.
'sc'+'holar'='SCHOLAR'
Can you help me to learn more?
(Other definitions for scholar that I've seen before include "Subject of poem by 1 across" , "Academic; pupil" , "Noted academic" , "Man of letters" , "Learned type" .)