I got your number

[Jesse Sheidlower]

On Tue, Nov 09, 2010 at 08:44:43PM +0100, Paul Frank wrote:
> Maybe it's just my looking up skills, but I don't find "I got your
> number," meaning "I know what you're up to" in any of my English
> dictionaries, including the OED.

I think this covers what you're looking for:

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P7. fig. to get (also take, etc.) a person's number: to have
or make an accurate assessment of a person's true character,
motives, weaknesses, etc. Cf. MEASURE n. 12b.

1853 DICKENS Bleak House lvii. 550 Whenever a person proclaims
to you ‘In worldly matters I'm a child,’..that person is only
a crying off from being held accountable, and..you have got
that person's number, and it's Number One. 1889 ‘M. TWAIN’
Connecticut Yankee xxxiv. 450 Let him go, for the present: I
took his number, so to speak. 1908 N.Y. American 9 Aug. S1/1
We have their number now..and they are due for a cleaning.
1920 W. HARD Raymond Robins' Own Story 190 To hurt Bolshevism
you need at least to get its number. 1970 G. JACKSON Let. 29
May in Soledad Brother (1971) 265 Big Brother. He is rather
transparent. I have his number. 1990 Independent 30 Jan. 19
She soon got the number of the football authorities... They
were..forever telling her why something could not be done.
---

Jesse Sheidlower
OED

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