At loggerheads

An expression meaning to be in serious disagreement or conflict.

A loggerhead was historically a long-handled iron tool with a bulbous end that could be heated, including for warming pitch aboard ships. The idea of people using such tools against one another is a proposed explanation for the idiom, but the specific story is not established conclusively.

The term does not refer to opposing ships secured by wooden rigging blocks. That explanation confuses the historical tool with unrelated fittings and should not be repeated as fact.