Sun used the term “瘪三” to describe Singapore uncles, which is a derogatory word typically used in Shanghai to describe the underclass bums in the society. It means a person who is a tramp, bum, good-for-nothing fella, beggar, drifter, loafer, outcast, vagrant, destitute and worthless person.
my goodness….. was just told the meaning for 傻逼. It is a dirty word concerning female genitals. I dare not write the full meaning here.