Green’s Dictionary of Slang

jack n.1

[later 20C+ usage is US black]

1. [late 15C+] a man or boy; a commoner as distinct from a gentleman.

2. [mid-17C] an acquaintance.

3. [late 17C] a general term of abuse.

4. [mid-18C+] as a term of address to a man [20C+ usage is primarily US].

5. [mid-19C] (Anglo-Ind.) a sepoy.

6. [mid-19C+] (US, also country jack) a rustic, a peasant; a simpleton [underpinned by jake n.1 (1)].

7. see jack tar n.2

In compounds

jack blunt (n.)

[late 19C–1910s] a blunt person.

jack boots (n.)

[early 19C] the ‘boots’ or bootboy at an inn.

jack bragger (n.) (also jack brag)

[mid–late 16C] a boaster, a braggart.

jack cove (n.) (also jake cove)

[late 18C–mid-19C] (UK Und.) a dirty, contemptible man.

jack fool (n.) [the term survived in 1940s Kansas dial.]

[17C] a foolish person.

jack gentleman (n.)

[late 17C–18C] a man of low birth or manners who has pretensions to be a gentleman, an insolent fellow, an upstart.

jack gentlewoman (n.)

[late 18C] a large masculine woman.

jack-hold-my-staff (n.)

[mid-17C] a fool.

jack mum (n.) [mum adj.]

[20C+] (Irish) a discreet person; esp. in the phr. between you and me and jack mum.

jack nasty (n.)

[mid–late 19C] a sneaking, slovenly person.

jack nasty face (n.) [punning on the general use, ‘a dirty fellow, seldom seen’ (J.Bee). Note merchant navy jargon jack nasty face, a cook’s assistant, or anyone considered ugly]

[19C] the vagina.

jack papish (n.) (also Jack Priest)

[early 18C–mid-19C] a derog. term for a Roman Catholic.

jack pudding (n.) [innate humour of a SE pudding]

[mid-17C–1910s] a jester or clown, travelling with a mountebank or itinerant quack .

jack-rat (n.)

[mid-19C] (UK Und.) a sneak-thief.

jack sauce (n.)

[mid-16C–early 18C] a saucy or impudent fellow.

jack stickler (n.)

[mid-16C–mid-17C] a meddlesome or interfering person, a busybody.

jack straw (n.) [ref. to Jack Straw, leader of the failed Peasants’ Revolt, 1381]

[late 16C–17C] a nonentity, lit. a ‘man of straw’.

jack weight (n.)

1. [mid-17C] in pl., the testicles.

2. [late 18C–19C] a fat man.

jack-whore (n.) (also jack mot) [mot n. (1)]

1. [mid-18C–mid-19C] a large, tough prostitute .

2. [mid-19C–1920s] a womanizer.

In phrases

fat jack of the bone-house (n.)

[mid-19C–1900s] a very fat man [obs. SE bonehouse, the human body].

jack-at-a-pinch (n.)

1. [late 17C–mid-19C] a temporary clergyman, hired when the regular incumbent is absent.

2. [mid-19C] one who is required only in an emergency or as a gapstop; thus an insignificant person.

3. [late 19C] an odd-job man.

jack at the stiff (n.)

[mid-19C] (UK Und.) a friend in need.

jack in the pulpit (n.) [SE pulpit, i.e. one who sets themselves up as a preacher, lit. or fig.]

[19C] a pretender, an upstart.

jack in the water (n.)

[mid–late 19C] a waterman’s attendant, who helps passengers on and off boats.

jack of clubs (n.)

[19C] (US) a good fellow, man.

jack of dover (n.)

[late 14C–17C] a Dover sole.

jack of legs (n.) [folk legend of Jack of Legs, a supposed giant, some 3m (14ft) tall, who is allegedly buried in the churchyard at Weston, Hertfordshire. A large thigh bone, excavated in the graveyard, was given to the naturalist Sir John Tradescant (1608–62)] [late 18C–19C]

1. a tall, long-legged man.

2. an outsize clasp-knife.

jack of the clockhouse (n.) [SE jack of the clockhouse, which ‘goes upon screws, and his office is to do nothing but strike’; the actual jack was a figure of a man which strikes the bell on the outside of a clock]

[17C] (UK Und.) a confidence trickster, specializing in selling supposedly purpose-written pamphlets, poems etc, which flatter the vanity of the purchaser but which are, in fact, mass-produced with a personalized dedication tacked on.

jack out of doors (n.)

[late 16C–17C] a vagrant, one who has been thrown out of his house.

jack-the-wrong-man (n.)

[mid-19C] (UK Und.) a policeman.

single-jack (n.)

[1920s–30s] (US tramp) a one-legged, one-armed or one-eyed beggar.