biological

1 of 2

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

biological

2 of 2

noun

bi·​o·​log·​i·​cal ˌbī-ə-ˈlä-ji-kəl 

variant of biologic

: a biological product (such as a vaccine or blood serum) used in medicine

Synonyms of biological

Adjective

• birth
• natural
• legitimate

Examples of biological in a Sentence

Adjective

the rights of the biological father in this case

Recent Examples on the Web

Adjective

Experimental skin cream linked to 2-year drop in biological age in early study. — FOXNews.com, 16 Oct. 2026

Researchers estimated in 2017 that simulating the ground-state energy of FeMoco, an iron-sulfur cluster involved in biological nitrogen fixation, would require roughly 50 trillion Toffoli gates. — Aamir Khollam, Interesting Engineering, 16 Oct. 2026

Noun

The three of them—the one biological that is mine and the other two—they’re doing great. — Julie Jordan, PEOPLE, 5 Aug. 2026

The lesson of spindle resilience extends beyond the biological. — Jake Buehler, Quanta Magazine, 29 June 2026

Word History

First Known Use

Adjective

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