bitter_end has definitions from the field of nautical
1
[ noun ] the final extremity (however unpleasant it may be)

Examples

"he was determined to fight to the bitter end"

Used in print

(James Boylan, "Mutinity"...)

This was the bitter_end , and Hudson seemed to know he was destined to failure .

Related terms

extremity

2
[ noun ] (nautical) the inboard end of a line or cable especially the end that is wound around a bitt

Related terms

end line seafaring

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