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

Spider also faces off with his villainous biological father, Colonel Quaritch (Stephen Lang), who jumps into a fiery chasm and meets an uncertain fate. —Patrick Ryan, USA Today, 20 Dec. 2025

The California Department of Education (CDE) has stood by its demand that the Tahoe Truckee Unified School District (TTUSD) switch sports associations to a league that allows biological male trans athletes to compete in girls sports. —Jackson Thompson, FOXNews.com, 19 Dec. 2025

Those interactions produced carbonate minerals, which can preserve chemical signatures of past environments and potentially of biological activity, scientists say. —Sharmila Kuthunur, Space.com, 19 Dec. 2025

Bees and wasps actually have amazing biological adaptations that allow each species to survive from year to year. —Arricca Elin Sansone, Southern Living, 19 Dec. 2025

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

• analogical
• astrological
• christological
• chronological
• cosmological
• cytological
• dialogical
• ecological
• ethnological
• ethological
• geological
• histological

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