Ask HN: What happened to 'effusive' in 1866?
If you do a Google search for 'effusive', and then click on 'Translations, word origin, and more definitions' you see the start of a hockey stick graph while 'effusive' gets users.
https://www.google.com/?gws_rd=ssl#q=effusive
What happened in 1866 that made this word popular? And why did growth hit a plateau around 1900?
Is there something we could learn about virality just by studying word popularity? I suspect it is related to the eruption of Krakatoa in 1883... According to the OED, effusive was used in GEOLOGY in the late 19th century. One particular reference in the extended entry is enlightening: 1888 F. H. Hatch in J. J. H. Teall Brit. Petrogr. 429 Effusive, a term lately used abroad for those rocks which have been poured out at the surface, the word eruptive now being generally used for the whole group of massive rocks. As noted, Krakatoa erupted in 1883. It was massive in sheer destructive force (though not quite as bad as Tambora in 1815, which remains the deadliest in recorded history). Still, it was a global phenomenon. Adding "krakatoa" to ngram reveals that it may just be tied to the spike, though perhaps this is just correlation. https://books.google.com/ngrams/graph?content=effusive%2Ckra... Coincidentally, today is also the day that Krakatoa started to erupt. It went on smoking for a few months before its infamous, earth shaking eruption. Hm, the ngram graph seems to show 'effusive' spiking well before Krakatoa, so I doubt that's the root explanation for the increase. If you dial down the smoothing, there is a blip right before Krakatoa's rise (1884-1887). Looking at the books from that time, it seems "effusive" was general parlance appearing in other places as well, including several popular elocution guides (of which Google records many versions). The blip dies out though, so it would seem that geologic and general science reporting are likely to be the ongoing source. Basic statistics. There are two factors at work here that obscure the real data: 1. The data is smoothed. Set the smoothing to 0 to see the real data. 2. The data is not absolute, but relative (note it's %) to the entire body of data Google has available for that year. The further back you go, the less overall data is available. I suspect strongly that the spikes you see are merely years where very few books overall are available. I don't see any clickable 'Translations, word origin, and more definitions'. Can you post a screen grab? I think this is what you are talking about though: https://books.google.com/ngrams/graph?content=effusive&case_... Nice! Right click the graph to aggregate it. Clickable link: https://www.google.com/?gws_rd=ssl#q=effusive Serendipitously, someone submitted a similar story just 3 minutes before: https://news.ycombinator.com/item?id=9573862 I wonder what caused submitting word definitions on Google suddenly become popular in mid-May of 2015. Seems it turned up in an elocution text of the time. Upward social amition + speech patterns. https://books.google.com/books?id=41RDAAAAYAAJ&pg=PA10&dq=%2...