Fossilized term

A fossilized term is a morpheme or a part of a morpheme that is obsolete and incomprehensible now but appears in a word or in an idiom. Some fossilized terms in English are shown below:

• fro in to and fro
• cob in cobweb, from the obsolete word coppe for a spider
• rasp in raspberry, from the obsolete word raspis for a raspberry