1. [late 17C–19C] trickery, fraud; usu. as understand trap ; up to trap
2. [18C–early 19C] one who blackmails a prostitute’s client.
3. [18C+] (also trapsman) usu. in pl., a policeman or similar agent of the law [metonymy].
4. attrib. use of sense 3.
5. [late 18C+] the mouth; esp. in phrs. keep one’s trap shut , shut one’s trap [it is a ‘trap’ for food, often used in combs., e.g. bread trap under bread n.1 , meat trap under meat n.].
6. [1920s+] a place, a house or apartment.
7. [1930s] (US tramp) a hiding-place for liquor or other illegal goods.
8. [1930s+] (US) a nightclub.
9. [1940s] (US black) the military draft during WWII.
10. [1960s] (drugs) a hiding place for drugs.
11. [1970s] a cubicle or stall in a public lavatory.
12. [1970s+] (US black) the number of customers a prostitute is assigned as a daily tally by her pimp to reach a financial target; thus the many she earns each night[i.e. those whom she SE traps].
13. (US black) money.
14. (US black / drugs) a place where drugs are dealt.
15. [2000s] the vagina.
16. see wolf-trap under wolf n.
[20C+] to be quiet.
[1930s–40s] to talk injudiciously, to boast.
[late 18C+] to be quiet; usu. as imper. shut your trap!
used by a potential victim, the trick has failed.
[late 17C–19C] to be aware, to know what is in one’s interest.
SE in slang uses
[mid-19C] (US Und.) a brothel where clients are robbed while in flagrante by an accomplice who reaches in through a concealed panel.
[1970s+] (US black) a prostitute’s daily earnings.
[1990s+] the anus; thus take it up trap two, to submit to anal intercourse.
1. to monitor a given situation, to oversee one’s business, esp. when it is illicit.
2. to spend time with a lover, esp. one with whom one is having an affair.
[1930s–60s] (Aus.) to make a tour of inspection.
[2010s] (US) at work.