What's the meaning of the phrase "got some big ones" in the sentence?

I happened to see this sentence in a subtitle of a movie, it said: "To think that you used an old man and a newbie as a decoy, you've sure got some big ones, don't you?". When i try to search the meaning of the phrase "big one", it just gives me something like: "a thousand dollars" or "an extremely large and destructive earthquake",... and i think they aren't suitable for the content in the sentence. What is the exactly meaning of the phrase "got some big ones" in this sentence?

Big ones (balls) refers metaphorically to courage, force.

Ball (slang)

a. Usually in plural. A testicle.

b**.** plural (frequently as a mass nou*n). *fig. and in extended use.

(b) orig. U.S. Virility, (manly) power or strength; substance, force, vigour. Also: courage, determination. Cf. ballsy adj.

• a1903 W. A. Henley in C. Harman R. L. Stevenson (2005) iv. 17 All eloquence and balls and brains; Heroic and also infantile.1928 D. H. Lawrence Lady Chatterley's Lover xiv. 236 You say a man's got no brain, when he's a fool... And when he's got none of that spunky wild bit of a man in him, you say he's got no balls. When he's sort of tame.1958 in H. Wentworth & S. B. Flexner Dict. Amer. Slang (1960) 17/1 (oral quot.) That copy is too weak. Rewrite it and put ballson it!1979 Tucson (Arizona) Mag. Jan. 29/3 I told him I just can't do it that way... I suppose it took balls, but it is no more balls than anyone should have for themselves.1984 M. Amis Money 315 Just keeping a handhold and staying where you are,..even that takes tons of balls.2006 Sunday Territorian (Austral.) (Nexis) 17 Dec. 38 Making a decision like that..takes a lot of balls.

Reddit.com (citing the OED)