biological

adjective

bi·​o·​log·​i·​cal ˌbī-ə-ˈlä-ji-kəl 

variants or less commonly biologic

ˌbī-ə-ˈlä-jik 

1

: of or relating to biology or to life and living processes

2

: used in or produced by applied biology

3

: connected by direct genetic relationship rather than by adoption or marriage

her biological father

biologically

ˌbī-ə-ˈlä-ji-k(ə-)lē 

adverb

Synonyms of biological

• birth
• natural
• legitimate

Examples of biological in a Sentence

the rights of the biological father in this case

Recent Examples on the Web

Lawyers for the groups backing the Olympus Spa have stated that the case comes down to whether women’s spaces may remain exclusive to biological women. — Jack Birle, The Washington Examiner, 13 Aug. 2026

Given so many biological, genetic and environmental influences, simply labeling someone as obese does little to explain that person’s overall health. — Daryl Austin, USA Today, 13 Aug. 2026

As of last fall, the brand was still featuring at least one biological male in lingerie during its show. — Joe Kinsey Outkick, FOXNews.com, 13 Aug. 2026

Now, 40 years later, a DNA test has shown that the childhood friends are biological sisters. — Reuters, NBC news, 12 Aug. 2026

Word History

First Known Use

1818, in the meaning defined at sense 1

Phrases Containing biological

• biological clock
• biological control
• biological oxygen demand
• biological parent
• biological warfare
• biological weapon
• non-biological

Rhymes for biological

• illogical
• zoological
• aetiological
• anthropological
• archaeological
• archeological
• axiological
• climatological
• deontological
• dermatological
• eschatological
• etiological

Kids Definition

biological

adjective

bi·​o·​log·​i·​cal

ˌbī-ə-ˈläj-i-kəl

variants also biologic

-ˈläj-ik

1

: of or relating to biology or to life and living things

2

: connected by a relationship involving heredity rather than by one involving adoption or marriage

his biological father

biologically

-ˈläj-i-k(ə-)lē

adverb

Medical Definition

biological

adjective

variants also biologic

1

: of or relating to biology or to life and living processes

2

: used in or produced by applied biology

3

: related by direct genetic relationship rather than by adoption or marriage

an adoptee who searched for years for her biological parents

biologically

-i-k(ə-)lē 

adverb