The Etymological Origins of Two-Part Words That Have One Part More Obscure That the Other

In an interesting episode of their incredibly informative whiteboard series for Mental Floss , linguist Arika Okrent and illustrator Sean O’Neill verbally and visually explain the etymological origins of words that were formed in parts and in which one of the parts is more obscure and/or not a word by itself. Examples include cobweb, twilight, cranberry, walnut, lukewarm and soothsayer

There are a number of words in English that seem to be formed from two parts, but one of the parts is obscure. Wonder no more at where these parts come from.