Green’s Dictionary of Slang

come-on n.

[SE excl. come on!]

1. [late 19C–1950s] (US Und.) a dupe, a victim of a confidence trickster; a prospective victim; a ‘steered’ prospect.

2. [20C+] (US Und., also come-on ghee) a con-man, a swindler; also attrib.

3. [20C+] (US) a snare, an inducement, a lure; also attrib.

4. [20C+] (US) patter or sales talk, a line; also attrib.

5. [1900s] a gullible fool.

6. [1930s+] (also come-in) a sexual invitation, either through a look or through words.

7. [1930s+] the personification of sense 6, a sexually alluring woman.

8. [1950s] a dare.

In compounds

come-on boy (n.)

[1940s+] a male prostitute who entices a client and then, instead of sex, has him beaten and robbed by a confederate.

come-on ghee (n.)

see sense 2 above .

come-on girl (n.)

[late 19C+] (US) a promiscuous woman; a prostitute.

come-on guy (n.) (also come-on man) [1920s–30s]

1. (US) the member of a confidence trickster team who lures the victim into the circle.

2. (US tramp) a hard worker, who encourages others.