Green’s Dictionary of Slang

up prep.

1. [late 17C; mid-19C+] having sexual relations with.

2. [1900s] of an object, offered, put in place.

3. [1930s+] at, e.g. up the market; occas. as adv.

In phrases

up each other (adj.)

[1940s+] (Aus.) indulging in mutual flattery.

up her like a rat up a drain(pipe) (also ...up a rhododendron) [1960s+] (orig. Aus.)

1. immediately involved in sexual intercourse, based on the assumption that a woman will be freely, easily and speedily sexually available to the speaker.

2. in non-sexual contexts, suggesting speed.

up it (adj.)

[1910s] highly emotional, at the end of one’s tether.

up one’s bum to the neck (adj.) [image of auto-sodomy]

[2000s] (N.Z.) self-important.

up on oneself (adj.)

[1900s] (US) proud.

up oneself (adj.) [image of auto-sodomy]

1. [1940s+] (orig. Aus.) arrogant, self-satisfied, full of oneself.

2. attrib. use of sense 1.

who’s up who (and who’s paying the rent)?

[1960s+] (Aus.) phr./ inquiring as to the sexual and montary underpinnings of a situation.

wouldn’t know if someone/something was up one

[1910s+] (Aus.) a phr. used of a very stupid person, usu. a woman, as she wouldn’t know if someone was up her.

In exclamations

up a flume!

[mid-19C] (US) a dismissive, insulting excl.

up your arse!/jumper!

see separate entries.