ulna

noun

ul·​na ˈəl-nə 

plural ulnae ˈəl-nē  or ulnas

: the bone on the little-finger side of the human forearm

also : a corresponding part of the forelimb of vertebrates above fishes

ulnar

ˈəl-nər 

-ˌnär

adjective

Examples of ulna in a Sentence

Recent Examples on the Web

Accomplishing even this step proved especially difficult because of the need to precisely align the volunteer’s radius and ulna. —Andrew Paul, Popular Science, 12 Oct. 2023

This air breathing fish’s front fins even have an ulna and a radius like our forearms do, and they’re coded by the same set of genes, reports Tessa Koumoundouros for Science Alert. —Alex Fox, Smithsonian Magazine, 27 Jan. 2021

Each one holds a skeleton laid out carefully to preserve the proper anatomical placement of bones—a radius must lie just next to the ulna on each table. —Ananda Rose, Scientific American, 1 June 2015

Dakotaraptor possesses a row of ‘quill knobs’, or papilli, on the surface of its ulna, one of the lower arm bones. —Jon Tennant, Discover Magazine, 2 Nov. 2015

Word History

Etymology

New Latin, from Latin, elbow — more at ell

First Known Use

1541, in the meaning defined above

Phrases Containing ulna

• radio-ulna

Kids Definition

ulna

noun

ul·​na ˈəl-nə 

plural ulnae -nē  or ulnas

: the bone on the little-finger side of the human forearm

also : a corresponding part of the forelimb of vertebrates

ulnar

-nər 

adjective

Medical Definition

ulna

noun

ul·​na ˈəl-nə 

plural ulnae -nē  or ulnas

: the bone on the little-finger side of the human forearm that forms with the humerus the elbow joint and serves as a pivot in rotation of the hand