deal (n.1)

"a part or portion," Middle English del, from from Old English dæl "a part of a whole, a share;" with qualification (great, etc.), "an extent, degree, quantity, amount," from Proto-Germanic *dailaz (source also of Old Norse deild, Old Frisian del "part; juridical district," Dutch deel, Old High German and German teil, Gothic dails "part, share, portion"), from PIE *dail- "to divide" (source also of Old Church Slavonic delu, Lithuanian dalis "part"), ‌‌perhaps a Northern Indo-European extended form of the root *da- "to divide," or perhaps a substratum word.

Formerly used in many senses now taken by part. Meaning "a share (of something), one's allotted portion" is from c. 1200. Business sense of "transaction, bargain" is 1837, originally slang, from the older sense of "arrangement among a number of persons for mutual advantage." In American history, New Deal is from Franklin D. Roosevelt's speech of July 2, 1932 (the phrase itself is by 1834). Big deal is from 1928 as "important transaction;" ironic use first recorded 1951 in "Catcher in the Rye." Deal-breaker is attested by 1975.

deal (n.2)

"plank or board," especially of fir or pine, late 14c., dele, from Low German (compare Middle Low German dele), from Proto-Germanic *theljon." From late 13c. in surnames. An Old English derivative was þelu"hewn wood, board, flooring."

deal (v.)

Middle English delen, from Old English dælan "to divide, distribute, separate;" hence "to share with others, bestow, dispense," and also "take part in, have to do with," from Proto-Germanic *dailjanan (source also of Old Saxon deljan, Old Frisian dela "to divide, distribute," Middle Dutch, Dutch deelen, German teilen, Gothic dailjan),from PIE *dail- "to divide," ‌‌perhaps a Northern Indo-European extended form of root *da- "to divide," or a word from a substrate language.

Meaning "to deliver (to another) as his share" is from c. 1300. Meaning "to distribute cards before a game" is from 1520s (the associated noun meaning "distribution of cards before a game" is from c. 1600). Hence colloquial deal (someone) in "include in an undertaking" (1942).

To deal with "handle, act toward (in some way)" is attested from mid-15c., from the notion of "engage in mutual intercourse, have to do with;" in late 14c. the phrase also mean "have sexual intercourse with." Related: Dealt; dealing.

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Definitions of deal
deal (v.)
act on verbally or in some form of artistic expression;
This book deals with incest
Synonyms: cover / treat / handle / plow / address
deal (v.)
take into consideration for exemplifying purposes;
Synonyms: consider / take / look at
deal (v.)
take action with respect to (someone or something);
How are we going to deal with this problem?
The teacher knew how to deal with these lazy students
deal (v.)
succeed in doing, achieving, or producing (something) with the limited or inadequate means available;
Synonyms: cope / get by / make out / make do / contend / grapple / manage
deal (v.)
administer or bestow, as in small portions;
deal a blow to someone
Synonyms: distribute / administer / mete out / parcel out / lot / dispense / shell out / deal out / dish out / allot / dole out
deal (v.)
do business; offer for sale as for one's livelihood;
She deals in gold
Synonyms: sell / trade
deal (v.)
be in charge of, act on, or dispose of;
I can deal with this crew of workers
Synonyms: manage / care / handle
deal (v.)
behave in a certain way towards others;
He deals fairly with his employees
deal (v.)
distribute cards to the players in a game;
Who's dealing?
deal (v.)
direct the course of; manage or control;
Synonyms: conduct / carry on
deal (v.)
give out as one's portion or share;
Synonyms: share / divvy up / portion out / apportion
deal (v.)
give (a specific card) to a player;
He dealt me the Queen of Spades
deal (v.)
deal hashish
deal (n.)
a particular instance of buying or selling;
he's a master of the business deal
it was a package deal
Synonyms: trade / business deal
deal (n.)
an agreement between parties (usually arrived at after discussion) fixing obligations of each;
he rose to prominence through a series of shady deals
Synonyms: bargain
deal (n.)
(often followed by `of') a large number or amount or extent;
a deal of trouble
Synonyms: batch / flock / good deal / great deal / hatful / heap / lot / mass / mess / mickle / mint / mountain / muckle / passel / peck / pile / plenty / pot / quite a little / raft / sight / slew / spate / stack / tidy sum / wad
deal (n.)
a plank of softwood (fir or pine board);
deal (n.)
wood that is easy to saw (from conifers such as pine or fir);
Synonyms: softwood
deal (n.)
the cards held in a card game by a given player at any given time;
Synonyms: hand
deal (n.)
the type of treatment received (especially as the result of an agreement);
he got a good deal on his car
deal (n.)
the act of distributing playing cards;
the deal was passed around the table clockwise
deal (n.)
the act of apportioning or distributing something;
the captain was entrusted with the deal of provisions