Plural of accession; items added to a collection, or the act of taking office or ascending to a position, especially a throne.
From accession, which comes from Latin accessionem (an addition), from accedere (to add to). The plural adds -s.
This word has split into two very different meanings: when you say 'the queen's accession,' you mean her assuming the throne, but a museum's 'recent accessions' means its new acquisitions—same word, totally different contexts!
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