1. [mid–late 19C] (UK Und.) to subject to surveillance, e.g. of criminals by the police.
2. [1910s+] (US Und.) to select a prospective victim.
3. [1950s–70s] (US black) to tease, to mock.
1. [1930s+] to watch someone, to place someone under surveillance, to pick someone out as a potential victim.
2. [1940s+] to explain, to point out, to warn.
3. [1960s+] to categorize, usu. either as a good or trustworthy or bad or untrustworthy person; to put someone in a specific position.
4. [1960s+] to realize, to see and understand.
1. [1910s+] to bruise, to leave with scars after a fight.
2. [1980s+] (Aus. prison) to tattoo.