in heat

1. In a state of sexual excitement immediately preceding ovulation. For example, Our cat's in heat so we have to keep her inside. This expression applies to most female mammals and indicates the period when the animal is fertile and most receptive to mating. [Mid-1700s]

Example Sentences

Exhibit two: their breeding is ridiculously difficult, given the narrow time frame—just two to seven days a year when the female is in heat and receptive to mating.

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“We need to send the pandas back to nature at different times to work out the best time for release. Plus, we believe females will be more welcomed by wild pandas when they are in heat.”

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This achievement confirms that material purity plays a decisive role in heat transfer performance and opens a path toward even more efficient heat-conducting materials.

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The Celtic powerbrokers, who have been engulfed in heat from the fans, knew what they were doing with this one.

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Another growing use case is in data centers, where aluminum is used in heat sinks, cooling systems and the structures themselves.

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