Definition of catkin in US English:



  • A flowering spike of trees such as willow and hazel. Catkins are typically downy, pendulous, composed of flowers of a single sex, and wind-pollinated.

    • ‘Pin oaks produce drooping wind-pollinated male flowers called catkins; the female flowers come in groups of one to three just as the leaves begin to unfold.’
    • ‘Some varieties shed pollen from the male catkins before the female flowers are receptive, and so require pollen from another variety with a later pollen maturation date.’
    • ‘They also eat fruits, berries, twigs, leaves, catkins, and seeds.’
    • ‘In winter, they are most readily observed feeding in trees with catkins, such as birch and alder.’
    • ‘Live oaks produce male flowers called catkins that bloom in hanging clusters.’


Late 16th century: from obsolete Dutch katteken ‘kitten’.