# heme

> English word · Noun · IPA /hiːm/ · frequency rank #54,830

## Definitions
1. The component of hemoglobin (and other hemoproteins) responsible for binding oxygen. It consists of an iron ion that binds oxygen and a porphyrin ring that binds the globin molecules; one molecule binds one molecule of oxygen.

## Etymology
Back-formation from hemoglobin.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/heme