“Break the ice” is a common idiom that means to get past formalities to get something accomplished or to reach a relaxed attitude in a socially awkward situation.
Example: David told a joke to break the ice at the beginning of the meeting.
Where did it come from?
This is another old nautical term; an allusion to forging a path through the ice for other boats to follow. River cities and seaports depended on ships and boats to transport goods and could become cut off if winter ice became too thick. Special vessels called “icebreakers” equipped for just the task were effective at breaking a path through the ice so trade could continue. Hence, breaking the ice was the precursor to getting business accomplished.
“To be the first to break the Ice of the Enterprize.”
“The Oratour – At last broke silence, and the Ice.”
The meaning flip flopped during the next 200 years that followed, but now the most allusion is applied to social situations more often than business.