TV is short for trichomonas vaginalis and is sometimes known as 'trich/trick'. Despite part of TV's name being 'vaginalis', men and women can get it although women exhibit more obvious symptoms.
Men might have a white penile discharge and perhaps a burning when urinating. Women tend to have the more obvious symptom of a frothy green vaginal discharge that's accompanied by a fishy smell. A woman might also have sore and inflamed vulva and vagina.
Some people claim that TV isn' always a transmitted sexually and that you can get it from hot baths, jacuzzis or from sharing towels. The evidence doesn't provide much support for this theory and by far the most common way of getting TV is through unprotected vaginal sex. There's a theoretical risk of catching TV from unprotected oral or anal sex too, but this is extremely rare.
To test for TV a doctor will normally take a genital swab and examine it under a microscope.
Antibiotics are normally prescribed to treat TV.