unconstitutional

adjective

un·​con·​sti·​tu·​tion·​al ˌən-ˌkän(t)-stə-ˈtü-sh(ə-)nəl 

-ˈtyü-

: not according or consistent with the constitution of a body politic (such as a nation)

an unconstitutional infringement on rights

unconstitutionality

ˌən-ˌkän(t)-stə-ˌtü-shə-ˈna-lə-tē 

-ˌtyü-

noun

unconstitutionally adverb

Examples of unconstitutional in a Sentence

an unconstitutional infringement of rights

The law may be unconstitutional.

Recent Examples on the Web

Federal government attorneys say the lawsuits are a backdoor way to regulate heat-trapping greenhouse gas emissions and amount to an unconstitutional power grab. — Lindsay Whitehurst, Arkansas Online, 4 Oct. 2026

A number of attorneys have echoed those concerns in lawsuits, arguing that the method is unconstitutional. — ABC News, 2 Oct. 2026

Blackburn also claimed that Smith’s appointment was unconstitutional. — Jack Birle, The Washington Examiner, 30 Sep. 2026

On Monday, former Commerce Secretary Wilbur Ross filed a lawsuit against the state, calling the tax unconstitutional. — Catherina Gioino, Fortune, 30 Sep. 2026

Word History

First Known Use

1734, in the meaning defined above

Rhymes for unconstitutional

• noninstitutional
• attributional
• constitutional
• convolutional
• distributional
• institutional
• involutional
• substitutional
• interinstitutional

Kids Definition

unconstitutional

adjective

un·​con·​sti·​tu·​tion·​al ˌən-ˌkän(t)-stə-ˈt(y)üsh-nəl 

-ən-ᵊl

: not according to or agreeing with the constitution of a state or society

unconstitutionality

-ˌt(y)ü-shə-ˈnal-ət-ē 

noun

unconstitutionally

-ˈt(y)üsh-nə-lē, 

-ən-ᵊl-ē

adverb

Legal Definition

unconstitutional

adjective

un·​con·​sti·​tu·​tion·​al ˌən-ˌkän-stə-ˈtü-shə-nəl, -ˈtyü- 

: contrary to or failing to comply with a constitution

especially : violative of a person's rights guaranteed by the U.S. Constitution

an unconstitutional search and seizure

unconstitutionality

-ˌtü-shə-ˈna-lə-tē, -ˌtyü- 

noun

unconstitutionally adverb