know beans about

English

know beans about (third-person singular simple present knows beans about, present participle knowing beans about, simple past knew beans about, past participle known beans about)

(chiefly US, in negative constructions) To know something, even if only a little, about.
- 1881 February 7, “Notes of the Fine Arts”, in New York Times, retrieved 22 September 2009, page 3:
  But the great artist doesn't know "beans" about driving oxen. He has put his driver on the "off" side of the yoke.
- 1963 March 12, “Dear Ann Landers”, in Pittsburgh Post-Gazette, retrieved 22 September 2009, page 17:
  If this self-styled expert in the field of human relations knew beans about handling people he'd get more work out of the women and fewer tears.
- 2008 July 14, Charles Paikert, “Ken Fisher”, in InvestmentNews, retrieved 22 September 2009:
  If wealth managers actually knew beans about anything, they would be in asset management.
(chiefly US, idiomatic) To know nothing, or almost nothing, about.
- 1986 August 22, “Editorial: The Cabinet Races”, in Gainesville Sun, retrieved 22 September 2009, page 18A:
  His primary opponent, Raphael Herman, is a real estate salesman who frankly admits he knows beans about insurance.

Often used in grammatical constructions containing a negative, as for example "He doesn't know beans about it."
Also simply "know beans", to know anything at all.
Sometimes emphasized by an extension, for example not know beans for buttons about.

to know nothing, or almost nothing, about