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

• 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

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

Other deciduous trees or fruit trees trained against a trellis, such as apples, pears, or ornamental trees, can benefit from the extra support during harsh winter winds. —Elizabeth Fogarty, Better Homes & Gardens, 21 Oct. 2025

In a sea of evergreens, these deciduous conifers blaze in brilliant shades of gold, standing out like lanterns against the darker forest. —Chantelle Kincy, Travel + Leisure, 14 Oct. 2025

Aspen groves are not as predominant here and hikers will find a wider array of colors due to the range of deciduous tree varieties fed by additional moisture from springs and creeks. —Roger Naylor, AZCentral.com, 10 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