the.com/partner

The other half of every plan, blamed for half the mess, credited for none of it.

means A person who shares an activity, business, relationship, or undertaking with you, with joint stakes in the outcome.

from From Old French 'parçonier' (a sharer or co-heir), rooted in Latin 'partitionem,' a sharing or dividing — the same 'part' you split when you split anything. English speakers reshaped the word toward 'part,' so a partner became, fittingly, someone who holds a part of what's yours.

latin root
From partir, meaning to share or divide
tax law
Partnerships dodge corporate tax, liability stays personal
crime usage
Accomplice and partner are legally distant cousins
dance halls
Tango requires zero words, total mutual surrender
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