1388: Invaluable and Valuable (LITW 6) Sep 29, 2018

Contronyms certainly do exist, when a word is its own opposite, like 'inflammable', but there are also words that have negating prefixes and mean the same thing, again like 'flammable' and 'inflammable', which can—though not necessarily will—mean the same thing. A common misconception is that 'invaluable' is synonymous with 'valuable', but this is not really true. Given that 'invaluable' means that it is so indispensable as to make it impossible to put a value or price on it, it is more precious than something merely valuable. In this way, while 'inflammable' and 'flammable' can synonymous or antonymous, 'invaluable' and 'valuable' are never truly synonymous, though neither are they totally opposite.

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