【明報專訊】A fossil is ''a remnant, impression, or trace of an organism of past geologic ages that has been preserved in the earth's crust''. Most fossils are of plants and animals, however the English language has fossils too. Fossil words are traces of older English buried in set phrases that have survived into the modern age. These fossil words are used, but are very difficult or impossible to find in most regular dictionaries. They're used in idioms, but rarely on their own.
Consider this sentence: ''The official denials are what our readers get ... often after a period of to and fro.'' The word fro means to go backwards or away from. The word is rarely used except in the idiom to go to and fro. The idiom describes an activity where people go backwards and forwards repeatedly, such as in walking, sports, shopping or trying to get information out of stubborn government officials.
Consider this headline: ''Trump's Syria strike justification shows executive branch run amok''. To run amok is a fixed idiomatic phrase. No one will ever walk amok; the word amok is not used on its own in English. The word amok is from the Malay amoq meaning fighting furiously. Today the phrase run amok means to behave in a violent or destructive and uncontrolled manner.
Fossil words are still used as part of an idiom and never, or rarely, used elsewhere. Idioms should be treated as words and remembered as an unchanging set. Fossil words are just part of that set phrase. Don't try to use fossil words elsewhere, unless you want to confuse people. As with idioms, fossil words should be recognised and managed. However it's best to avoid using them with second-language learners, in business contracts or any time clarity is more important than language art.
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