British slang <n> (Offensive)
The only externally visible part of the urethra on a male where semen and urine is secreted from the body.
Known as a 'Jap's eye' due to the similarity between the shape of the stereotypical Japanese eye and that the opening on the
penis is much like a slit.
Although the phrase is not used in a directly racist manner,
people of Far Eastern origin
may take offence to the use of the term.