Hilary is a boys name that became a girls name. It is also a surname (although the latter usually has a double L).

Hilary is an interesting case because, in the data the article is looking at, there are only 5 total years where there were more M Hilarys than Fs: 1936-1941. And even in 1936 the M:F Ratio was only 28:9 (that's not a reduced fraction; the total count was 37). If it's true that Hilary was once a popular boys name, the evidence for that claim is not in the SSA data.

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graemep 15 hours ago | parent [-]

I think that data only goes back to 1936? its too recent.

It may also have been more popular in the UK than the US.

	▲	gregates 6 hours ago \| parent [-]
		SSA data goes back to 1880, but it's incomplete before 1936 (only counting people who applied for social security after birth). Presumably that's why the article uses 1936 as their data cutoff.