The phrase
"unfettered expansion" means a growth or increase without any restrictions or limitations. It refers to the idea of free and unrestricted expansion or development.
Full definition
The report held the assumption that
unfettered expansion of the Alberta tar sands would happen regardless of politics, economics, or the climate.
The 2000s saw
an unfettered expansion from a simple trio of...
But since
the unfettered expansion and experimentation of the early seventies, Tourism has become its own international industry.
Publishers Weekly - Randers has made it his life's work to caution the world about the dangers of
unfettered expansion, and to seek out solutions to current and prospective problems.