the.com/deal

a handshake disguised as math, where both sides quietly believe they won

means An agreement or arrangement between parties, especially one involving an exchange or transaction; also the act of distributing or handing out (as cards).

from From Old English 'dǣlan,' to divide, share, or distribute — itself from 'dǣl,' a part or portion, a cousin of German 'Teil' (part) and 'teilen' (to divide). The thread runs straight through: to deal once meant simply to dole out shares, which is still why you 'deal' cards into hands. Only later did the sense narrow toward a struck bargain — the portion each party carries away from the table.

origin
From Old English dǣlan, meaning to divide or share
card game
To deal once meant literally portioning out anything, not just cards
new deal
FDR's 1933 program reshaped American government in a single phrase
psychology
Both parties feel they won in well-designed negotiations
phrase
Big deal originally meant exactly that, not sarcasm
for instance

new deal — fdr's 1933 program that created 15 major agencies to combat the great depression

iran nuclear deal — 2015 jcpoa agreement between iran and six world powers limiting iran's nuclear program

good friday agreement — 1998 peace accord that ended the northern ireland conflict

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