bilirubin

American  

[bil-uh-roo-bin, bil-uh-roo-bin] / ˈbɪl əˌru bɪn, ˌbɪl əˈru bɪn /

noun

Biochemistry.

1. a reddish bile pigment, C 33 H 36 O 6 N 4 , resulting from the degradation of heme by reticuloendothelial cells in the liver: a high level in the blood produces the yellow skin symptomatic of jaundice.

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bilirubin British  

/ ˌbɪlɪˈruːbɪn, ˌbaɪ- /

noun

1. an orange-yellow pigment in the bile formed as a breakdown product of haemoglobin. Excess amounts in the blood produce the yellow appearance associated with jaundice. Formula: C 32 H 36 O 6 N 4

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bilirubin Scientific  

/ bĭl′ĭ-ro̅o̅′bĭn /

1. A reddish-yellow pigment that is a constituent of bile and gives it its color. Bilirubin is a porphyrin derived from the degradation of heme. It is often a constituent of gallstones, and also causes the skin discoloration seen in jaundice. Chemical formula: C ₃₃ H ₃₆ N ₄ O ₆ .

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Etymology

Origin of bilirubin

< German Bilirubin (1864), equivalent to Latin bīli ( s ) bile + rub ( er ) red + German -in -in ²

Example Sentences

In a Phase 3 clinical trial, two patients out of a total 2,000 recorded high levels of alanine aminotransferase and bilirubin, typically a strong predictor of liver failure.

From Barron's • Apr. 15, 2026

Children are basically exposed to ultra-violet light to dissolve the excess bilirubin in their red blood cells.

From BBC • Jan. 7, 2025

This is caused by a build-up of bilirubin, a yellow substance, in the blood, meaning the babies' skins have a yellow tinge.

From BBC • Jan. 7, 2025

“Now that we’ve identified this enzyme, we can start investigating how the bacteria in our gut impact circulating bilirubin levels and related health conditions like jaundice,” said Xiaofang Jiang, the study’s co-author.

From Salon • Jan. 4, 2024

Urobilin is the coloring matter extracted from the urine in fever by Jaff�, and it has since been obtained from bilirubin by Maly,42 who has given it the name of hydrobilirubin.

From A System of Practical Medicine by American Authors, Vol. I Volume 1: Pathology and General Diseases by Various