Definition

1. Noun:
   • A recurring period in female nonhuman mammals characterized by physiological and behavioral changes indicating readiness to mate. This state involves heightened sexual receptivity and activity, often synchronized with ovulation.

Usage Examples

• Noun:
  • The veterinarian noted that the dog was in estrus.
  • Researchers study hormonal changes during the estrus cycle of rodents.
  • The female cat's estrus is often signaled by increased vocalization.

Advanced Usage

• "To be in estrus": Describes the state of a female mammal experiencing this period of sexual receptivity.
  • The zoo monitors when its lions are in estrus for breeding programs.
• "Estrus cycle": Refers to the entire recurring physiological series of changes, including estrus and non-receptive phases.

Variants and Related Words

• Estrus is the primary spelling in American English. The variant spelling oestrus is common in British English.
• Estrous (adj): Pertaining to or characteristic of estrus.
  • Scientists observed estrous behavior in the herd.
• Anestrus (n): A period of sexual inactivity between estrus cycles.
• Polyestrus (adj): Having multiple estrus cycles in a mating season or year.

Synonyms

• Heat (n): A common informal synonym, especially in the context of domestic animals.
• Rut (n): While sometimes used broadly, "rut" more specifically refers to the mating period in male mammals. For females, "estrus" is the precise term.

Related Terms and Concepts

• Ovulation (n): The release of an egg, which typically occurs during or near estrus.
• Receptivity (n): The state of being willing to accept mating, a key behavioral component of estrus.
• Cycle (n): Often used in the compound term "estrous cycle" to describe the full reproductive sequence.

Noun

1. applies to nonhuman mammals: a state or period of heightened sexual arousal and activity