Landmass and sea air swirling, full of uranium (7)
I believe the answer is:
eurasia
'landmass' is the definition.
(Eurasia is an example)
'sea air swirling full of uranium' is the wordplay.
'swirling' indicates anagramming the letters.
'full of' is an insertion indicator.
'uranium' becomes 'u' (U is the chemical symbol for uranium).
'sea'+'air'='seaair'
'seaair' anagrammed gives 'erasia'.
'erasia' going around 'u' is 'EURASIA'.
'and' is the link.
(Other definitions for eurasia that I've seen before include "Turkey, and so on" , "Huge area" , "large part of world" , "Unbroken landmass bearing two continents" , "Continental land mass" .)