Our News

Safe deposit box or safety deposit box?

6 September 2017

When researching last year the history of the safe deposit box, Christopher Barrow of Metropolitan Safe Custody became intrigued by references to ‘safety’ deposit boxes. Which is right?

Wikipedia, the free encyclopedia, takes the view that a “safe deposit box” is “sometimes known erroneously as a safety deposit box”. On the other hand, conventional dictionaries, whether British or American, do not appear to imply any such error. Within the industry, “safe deposit box” is the generally accepted term in the UK, whereas “safety deposit box” is more commonly used in the United States.

The latter’s more prominent use in America may perhaps explain the Collins English Dictionary’s reference to “safety-deposit box” as “US another name for safe deposit box”. That said, Cambridge Dictionary, another British publisher, simply refers to “safe deposit box (also safety deposit box)”. Similarly, America’s Merriam-Webster makes mention of a “safe-deposit box” as being “called also safety-deposit box”.

Is Wikipedia correct in referring to a “safety deposit box” as erroneous? Does it matter if it is a spelling mistake? After all, spelling is the forming of words from letters “according to accepted usage”, which has become the case with “safety deposit box”, especially in the US. However, the offending phrase is not actually a misspelling at all. It appears to be a misplaced phrase in the sense that it creates a meaning that does not make grammatical sense.

The reason that the phrase “safety deposit box” is incorrect is that the word “safety” is a noun, which, unlike the adjective “safe”, should not be used to describe another noun “deposit box”. By the same token, the use of a hyphen also makes no sense when it comes to “safety-deposit” because the noun “safety” should not be used to describe “deposit”. On the other hand, “safe-deposit” or “safe-deposit box” is perfectly correct as it is grammatically a ‘compound adjective’ made up of an adjective and a noun.

What appears to have happened (probably over a considerable time period) has been a continuous mishearing of “safe deposit box”, whereby the first two syllables “safe de…” sound like “safety” to become pronounced phonetically as “safety posit box”, which would have evolved into the ungrammatical “safety deposit box”.

In phonetics, it is called the ‘assimilation’ process, by which a speech sound, especially in rapid speech, becomes similar or identical to a neighbouring sound. It can occur either within a word or between words. In some cases, the change in transcription makes for incorrect English, such as “safety deposit box”, because the resulting word, phrase or sentence is grammatically wrong.

The use and development of language is an interesting subject, but it can be argued that it has increasingly less business or social relevance in today’s internet age. A topical example is that, for families wanting to store their valuables in a suitable vault, it hardly matters what phrases or “keywords” they use in their internet search. The holy grail of online search is now for websites to deliver upon the requirements of people based on them providing remarkably little information. The term “safety deposit box” may be erroneous, but the extraordinary world of SEO algorithms will no doubt deliver on your search request without incurring the wrath of your old English teacher!