Derailleur gears operates the lever while pedalling, the change in cable tension moves the chain-guide from side to side, "derailing" the chain onto different sprockets. For more information about the choice of particular gear ratios and sprocket sizes, see Bicycle gearing. "Derailleur" is a French word, spelled "dérailleur" in French, derived from the derailment of a train from its tracks. Its first recorded use was 1930. At least one notable bicycle industry author has attempted to promote the anglicized spelling of "derailer". As of 2013, however, neither Merriam-Webster nor the Oxford English Dictionary has an entry for "derailer". Various derailleur systems were
French articles and determiners the English definite article "the", although they are sometimes omitted in English. The French definite article can vary according to the gender (feminine or masculine) and number (singular or plural) of the noun. The definite article takes the following forms: Like "the", the French definite article is used with a noun referring to a specific item when both the speaker and the audience know what the item is. It is necessary in the following cases: Unlike "the", the French definite article is also used with mass nouns and plural nouns with generic interpretation, and with abstract nouns. For example: The