Q: Is “for” or “in” preferred in a sentence like this one: “I haven’t seen him in/for years.” I believe “for” is more common in Britain, while “in” is more common in the US.
A: The prepositions “in” and “for” have both been used since at least the 1400s to indicate durations of time. In fact, the Oxford English Dictionary gives “for” as a meaning of “in” when used this way.
Although this “in” usage was once seen only in negative sentences (like the one you mention), it’s now used both negatively and positively, according to the OED.
The dictionary doesn’t label this usage as slang or as an Americanism. In other words, it’s standard English on both sides of the Atlantic.
Nevertheless, it’s clear from googling “I haven’t seen him in years” and “I haven’t seen him for years” that “for” is indeed much more common on UK websites, while both “in” and “for” are commonly used on US sites.
The first published reference in the OED showing “for” used to indicate the length time is in a medieval mystery play dating from around 1450: “Who seyth oure ladyes sawtere dayly for a yer thus.”
The earliest OED citation for “in” used this way is from Sir Thomas Mallory’s Le Morte d’Arthur (1470-85): “He made them to swere to were none harneis in a twelue monethe and a day.”
But that’s just the beginning. The dictionary has a dozen citations for the “in” usage over 500 years, including a March 1, 1669, diary entry in which Samuel Pepys writes of returning “to Westminster Hall, where I have not been, I think, in some months.”
All the print references are negative until this one from a 1971 article in the Daily Telegraph that refers to the “first bridge across the Bosphorus in 2,300 years.”
That was the last British citation for the “in” usage. The two OED citations since then – one positive and the other negative – are from American sources.
The negative one is from Ed McBain’s novel Sadie When She Died (1972): “Arlene said that she had not played tennis in three years.”
The positive cite is from a 1973 article in Scientific American: “When Mariner 9 reached Mars on November 13, 1971, the greatest dust storm in more than a century was raging.”
In summary, it’s OK to use either preposition in a sentence like “I haven’t seen him in/for years.” But “for” seems to be more popular in Britain today, while both “in” and “for” are common in the United States.
By the way, I’ve written several blog entries about differences between American and British English, including one about the use of prepositions.
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