Try your best to distinguish tights from these very similar clothing forms.
Pantyhose is an American term for garments that take the form of tights, but are thinner, and more sheer than tights. Pantyhose and tights are functionally a form of underwear intended to be worn under bottomwear. The main difference between tights and pantyhose is the thickness of the material. In some countries, the term `tights` refers to both thin, and thick constructions.
Performers will prefer to wear tights over pantyhose. Pantyhose is more commonly associated with lingerie, and bunny costumes. http://www.differencebetween.net/miscellaneous/fashion-beauty/difference-between-pantyhose-and-tights/
Leggings are essentially legwear that essentially function as tight pants similar to yoga pants. Unlike tights, leggings do not cover the feet, and are thick enough to be worn casually without bottomwear. Most real leggings are not translucent. http://www.differencebetween.net/miscellaneous/fashion-beauty/difference-between-yoga-pants-and-leggings/
Yoga pants are tight pants similar to leggings, but usually have a flared pantleg. Yoga pants have a waistband, and are more flexible than leggings. 
