Green’s Dictionary of Slang

down adv.2

[orig. Und. down cove, a potential victim of a robbery who is aware of being targeted. Originating among late-18C London criminals, the term survives mainly among US blacks]

1. [late 18C+] (also downish) aware, conscious of, knowledgeable; thus be down upon, to be aware, to be knowledgeable; in 1940s+ use, to be part of the current (youth) fads and fashions.

2. [mid-18C] suspicious.

3. [mid-19C+] first-rate, excellent.

4. [1940s+] (US black) alert, keen to get on, tough, challenging in a fight.

5. [1950s+] willing (to do something), enthusiastic.

6. [1950s+] (US black) fashionably dressed, chic.

7. [1960s] (US black) interesting, current.

8. [1960s+] (US) happening, going on.

9. [1970s+] worked out in a satisfactory manner, under control, going well.

10. [1990s+] (US) in a relationship.

11. [2000s] (US black) feeling well, happy, at one with the world.

In derivatives

downish (adj.)

see sense 1 above.

In compounds

down-ass (adj.) [-ass sfx]

[1980s+] (US black) a general term of approval.

downmouth (v.) [sense 2 above/down n.2 (2) + SE mouth]

[1980s] (US) to attack verbally, to slander.

In phrases

ain’t down with

[1980s+] (US black/campus) used when referring to a situation one does not particularly like, e.g. I ain’t down with this idea!

down as a hammer/nail/trippet

[early–mid-19C] very well aware.

down by law [1980s+] (orig. US black)

1. expert, professional (within one’s occupation).

2. describing a wholly admirable person, object or idea.

down for

[1950s+] (US black) loyal to, committed to, in favour of.

down for mine [mine n.]

[1950s+] (orig. US black) able to look after oneself.

down on the case

[1970s] (US black) fully aware, completely knowledgeable.

down (up)on [sense 2 above/down n.2 (2)]

1. [18C–19C] attacking physically.

2. [mid-19C+] annoyed with, disappointed in, holding a negative opinion of.

down upon

[late 18C+] aware, knowledgeable.

down with (orig. US black)

1. [1930s–40s] through with.

2. [1940s+] involved with, agreeable to.

3. [1940s+] empathetic, emotionally responsive; enjoying, appreciating.

4. [1990s+] (US) friendly with.

have something down (v.)

[late 19C+] to be aware of the situation, to know what is going on.

put down (v.)

[early 19C; 1970s] (UK/US Und., to convey information to someone, to explain, to make someone aware; thus UK Und.) put a swell down, to alert one’s target (typically the target of a pickpocket) that one is about to rob them.