crab

noun (1), often attributive
\ˈkrab \

Definition of crab 

(Entry 1 of 5)

1 plural crabs also crab : any of numerous chiefly marine broadly built decapod crustaceans:

a : any of an infraorder (Brachyura) with a short broad usually flattened carapace, a small abdomen that curls forward beneath the body, short antennae, and the anterior pair of limbs modified as grasping pincers

b : any of various crustaceans of an infraorder (Anomura) resembling true crabs in the more or less reduced condition of the abdomen

2 capitalized : cancer sense 1

3 crabs plural : infestation with crab lice

4 : the angular difference between an aircraft's course and the heading necessary to make that course in the presence of a crosswind

crab

verb (1)
crabbed; crabbing

Definition of crab (Entry 2 of 5)

intransitive verb

1 : to fish for crabs

2a(1) : to move sideways indirectly or diagonally

(2) : to crab an airplane

b : to scuttle or scurry sideways

transitive verb

1 : to cause to move sideways or in an indirect or diagonal manner specifically : to head (an airplane) into a crosswind to counteract drift

2 : to subject to crabbing

crab

noun (2)

Definition of crab (Entry 3 of 5)

crab

noun (3)

Definition of crab (Entry 4 of 5)

: an ill-tempered person : grouch

crab

verb (2)
crabbed; crabbing

Definition of crab (Entry 5 of 5)

transitive verb

1 : to make sullen : sour old age has crabbed his nature

2 : to complain about peevishly

3 : spoil, ruin

intransitive verb

: carp, grouse always crabs about the weather

Other Words from crab

Verb (1)

crabber noun

Verb (2)

crabber noun

First Known Use of crab

Noun (1)

before the 12th century, in the meaning defined at sense 1

Verb (1)

1657, in the meaning defined at intransitive sense 1

Noun (2)

14th century, in the meaning defined above

Noun (3)

1580, in the meaning defined above

Verb (2)

1662, in the meaning defined at transitive sense 1

History and Etymology for crab

Noun (1)

Middle English crabbe, from Old English crabba; akin to Old High German krebiz crab and perhaps to Old English ceorfan to carve — more at carve

Noun (2)

Middle English crabbe, perhaps from crabbe crab entry 1

Verb (2)

Middle English crabben, probably back-formation from crabbed

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Learn More about crab

Dictionary Entries near crab

CR

cr

Cr

crab

crab's claw

crab's-eye

crab's-eye vine

Statistics for crab

Look-up Popularity

Time Traveler for crab

The first known use of crab was before the 12th century

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More Definitions for crab

crab

noun
\ˈkrab \

Kids Definition of crab

 (Entry 1 of 3)

: a sea animal that is a crustacean related to the lobsters and has a short broad flat shell and a front pair of legs with small claws

crab

noun

Kids Definition of crab (Entry 2 of 3)

: a person who is usually grouchy

crab

verb
crabbed; crabbing

Kids Definition of crab (Entry 3 of 3)

crab

noun
\ˈkrab \

Medical Definition of crab 

1 : any of a tribe (Brachyura) of chiefly marine crustaceans with a short broad usually flattened carapace, a small abdomen that curls forward beneath the body, short antennae, and the anterior pair of limbs modified as grasping pincers

2 crabs plural : infestation with pubic lice

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More from Merriam-Webster on crab

Rhyming Dictionary: Words that rhyme with crab

Thesaurus: All synonyms and antonyms for crab

Spanish Central: Translation of crab

Nglish: Translation of crab for Spanish Speakers

Britannica English: Translation of crab for Arabic Speakers

Britannica.com: Encyclopedia article about crab

Comments on crab

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