What is a blocking bill?

a bill placed early on the senate calendar that will never be considered by the full senate. Its purpose is to require 2/3 of the senators to vote to suspend the senate rule that requires bills to be taken off the calendar in chronological order. The effect is that any bill appearing later on the calendar must have the support of 2/3 of the senate if it is to be allowed to come up for debate and passage

me no say