exhaustive
The environmental impact of the proposed road was studied exhaustively.
The story was exhaustively researched by a reporter whose reputation for honest reporting is unquestioned.
It wasn't possible to exhaustively test how effective this technology is.

SMART Vocabulary: related words and phrases

Complete and whole
(all) in one pieceidiom
aggregate
all or nothingidiom
all toldidiom
all-in-one
all-inclusive
fell
fibre
full strength
full-length
fully
fully fledged
globally
systemic
thoroughgoingly
thoroughly
through and throughidiom
to the lastidiom
totality
toto