Idiom Definition:
  
    
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"to be full of hot air"  
    to talk nonsense
    to say things that are not true
    to exaggerate
     
Synonyms:
arrogant, big-headed, blow-hard, boast, boaster, bombastic, brag,  braggart, embroider, grandiloquent, grandstand, inflate, know-it-all, long-winded, loquacious, motor-mouth, redundant, repeating, repetitious, repetitive, rhetorical, show-off, stretch, talkative, tedious, verbose, windbag
 
 
This hot air balloon is literally 
full of hot air. - - - - ->  
