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

In this Corporate Era, cyborgs (humans with both biological and artificial parts) and synthetics (humanoid robots with artificial intelligence) exist alongside humans. — Rosy Cordero, Deadline, 9 July 2026

The film tells the story of a Swiss adoptive mother and her son, who travel to South Korea to meet his biological mother. — Leo Barraclough, Variety, 9 July 2026

Women are stepping back from leadership roles, withdrawing from opportunities, and quietly losing trust in their own judgment in response to a biological event nobody told them was biological. — Dr. Sarah Berg, Time, 9 July 2026

For cultural and biological reasons, female tennis players far more commonly take sabbaticals. — Josh Levin, The Atlantic, 9 July 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