male (animal, plant)
「雄」 has other readings with different meanings.
male
male; man
female
この柴犬は雄でまだ生後一年の若い子犬です。
This dog is male and still young.
雄のライオンは立派なたてがみを持つ。
Male lions have magnificent manes.
夏休みの昆虫採集で大きなカブトムシの雄を捕まえた。
I caught a male rhinoceros beetle.