Definition of ESTRUS. : a regularly recurrent state of sexual excitability during which the female of most mammals will accept the male and is capable of conceiving: heat; also: a single occurrence of this state. See estrus defined for kids.
1. (medicine) any of various liquids sold as medicine (as by a travelling medicine show) but medically worthless. 2. communication (written or spoken) intended to deceive. Familiarity information: SNAKE OIL used as a noun is rare. Dictionary entry details.
Fish oil is one of the most common supplements taken in the U.S., but is it just snake oil in disguise? Something's fishy in the world of supplement marketing, and it's difficult to know if the benefits and health claims on the packaging are for real or just false advertising.