Marrow

Part of speech: noun

Pronunciation: /ˈmæɹəʊ/

Definitions

1. The nutritious tissue inside bones plays a key role in blood cell formation and fat storage
2. Located in the cavities of bones, this soft substance is essential for generating blood cells and maintaining fat reserves
3. The soft, fatty substance within bones serves vital functions including the production of blood cells and the storage of fats

Etymology: The fact that stands out is how far this word reaches across languages. Old English "mearg" named the soft tissue inside bones, and its relatives appear in West Frisian "moarch", Dutch "merg", German "Mark", Swedish "märg" and Icelandic "mergur". Look further east and the same root turns up meaning brain: Russian "мозг" (mozg) and Polish "mózg", and even Persian "مغز" (maġz) and Sanskrit "मज्जन्" (majján). That spread suggests the word goes back to an ancient ancestor, though the earliest form is reconstructed rather than attested. English also picked up a second form from Old Norse "margr", which lies behind the variant spellings that competed with the native word in Middle English, "mary", "marow" and "marwe". The Old Norse and Old English words are closely related, so the two streams reinforced one another rather than competing for meaning. The word is also a doublet of "maghaz", a related form that came into English by a separate route, so the two entries show two different paths from the same ancestral root.

Synonyms: essence, core, substance, pith, heart

Antonyms: shell, exterior, surface