Like a hot knife through butter means something happens very easily and smoothly, with little effort or resistance. It describes a situation where a task or action works perfectly and quickly.
The expression stems from the way a warm knife cuts through butter without any struggle, as it melts it as it cuts.
The expression stems from the way a warm knife cuts through butter without any struggle, as it melts it as it cuts.
The new mower went through the long grass like a hot knife through butter.