Sesquicentennial
/ˌsɛskwɪsɛnˈtɛn.i.əl/noun
A 150th anniversary or its celebration.
Did you know?Its first element, Latin sesqui-, is an ancient numerical prefix meaning “one and a half,” a relic of Roman counting that still survives in technical words like sesquialter and sesquipedalian.
Etymological Timeline
Latin
Latin
sesqui-
“one and a half”
Latin
Latin
centum
“one hundred”
Late Latin / Neo-Latin
Latin
sesquicentum
“one hundred and fifty”
19th Century
English
sesquicentennial
“a 150th anniversary or celebration”
Modern English
English
sesquicentennial
“a 150th anniversary or its observance”
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