Hype broadcast that is plain (7)
I believe the answer is:
prairie
'plain' is the definition.
(I've seen this before)
'hype broadcast that is' is the wordplay.
'hype' becomes 'PR' (abbreviation for public relations).
'broadcast' becomes 'air' (synonyms).
'that is' becomes 'i.e.' (synonyms).
'pr'+'air'+'ie'='PRAIRIE'
(Other definitions for prairie that I've seen before include "Continental grassland of N America" , "Large treeless tract of grassland" , "Cowboy song: ` `Bury me not on the lone .......' '" , "Grasslands" , "Great grassland area" .)