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

But this month, the Coalition for Open Democracy, a voter advocacy group, filed a lawsuit, arguing the New Hampshire law is unconstitutional for burdening eligible students' right to vote and discriminating against younger voters for their age. — Hansi Lo Wang, NPR, 17 Aug. 2026

Unsurprisingly, one lower court has said that the order appears to be an unconstitutional use of Presidential power. — Amy Davidson Sorkin, New Yorker, 16 Aug. 2026

The defense previously argued all the items in Mangione's backpack were obtained in an unconstitutional search, but judges in both the federal and state cases disagreed. — ABC News, 15 Aug. 2026

Because the tax was not apportioned among the states as the Constitution required, those provisions were unconstitutional. — Kelly Phillips Erb, Forbes.com, 15 Aug. 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