Line offered by Boris, panicked about answer? (6)
I believe the answer is:
isobar
'line' is the definition.
(isobar is a kind of line)
'boris panicked about answer?' is the wordplay.
'panicked' indicates an anagram.
'about' is an insertion indicator.
'answer?' becomes 'a' (abbreviation eg in Q and A).
'boris' with letters rearranged gives 'isobr'.
'isobr' enclosing 'a' is 'ISOBAR'.
'offered by' is the link.
(Other definitions for isobar that I've seen before include "meteorologist's line" , "Map line showing atmosphere pressure" , "Barometric curve" , "Meteorological line joining points of equal pressure" , "Equal-pressure line" .)