deciduous

adjective

de·​cid·​u·​ous di-ˈsi-jə-wəs 

-jü-əs

1

biology : falling off or shed seasonally or at a certain stage of development in the life cycle

deciduous leaves

deciduous scales

2

biology

a

: having deciduous parts

maples, birches, and other deciduous trees

deciduous dentition

b

: having the dominant plants deciduous

a deciduous forest

3

: ephemeral

There is much that is deciduous in books …

—J. R. Lowell

deciduousness noun

Synonyms of deciduous

• temporary
• flash
• brief
• transient
• passing
• ephemeral
• transitory

Examples of deciduous in a Sentence

the bare branches of a deciduous tree in winter

he chose not to fret about the deciduous discomforts of his existence

Recent Examples on the Web

One study of yellow mutants of three deciduous species, for example, found that more nitrogen was left behind in their yellow leaves than in the normal red leaves. —Nell Greenfieldboyce, NPR, 5 Nov. 2025

Witch Hazel Witch hazel (Hamamelis virginiana) is a type of small deciduous shrub or tree that features fragrant yellow flowers that bloom on old growth from fall to spring, depending on the type. —Karen Brewer Grossman, Southern Living, 3 Nov. 2025

Evergreens, which hold their foliage all year, don’t get the same energy break that deciduous plants do. —Erica Browne Grivas, Better Homes & Gardens, 1 Nov. 2025

This is a deciduous vine that prefers a shady exposure, sips water, and will happily clamber up the branches of a native oak or any other tree. —Joshua Siskin, Oc Register, 25 Oct. 2025

Word History

Etymology

Latin deciduus, from decidere to fall off, from de- + cadere to fall — more at chance

First Known Use

1657, in the meaning defined at sense 1

Phrases Containing deciduous

• deciduous tooth

Kids Definition

deciduous

adjective

de·​cid·​u·​ous di-ˈsij-ə-wəs 

1

: falling off (as at the end of a growing period or stage of development)

antlers are deciduous

deciduous leaves

2

: having deciduous parts or members with deciduous parts

deciduous trees

a deciduous forest

Medical Definition

deciduous

adjective

de·​cid·​u·​ous di-ˈsij-ə-wəs 

1

: falling off or shed at a certain stage in the life cycle

2

: having deciduous parts

a deciduous dentition