Majestic and terribly large (5)
I believe the answer is:
regal
'majestic' is the definition.
(synonyms)
'terribly large' is the wordplay.
'terribly' is an anagram indicator.
'large' with letters rearranged gives 'REGAL'.
'and' acts as a link.
(Other definitions for regal that I've seen before include "Fit for a monarch" , "King-like" , "Royal - lager (anag)" , "Befitting a monarch" , "Magnificent, dignified" .)