To make something eternal or cause it to last forever; to preserve in memory or record permanently (British spelling).
From eterne/eternal plus -ise suffix (British spelling of -ize). The verb form allows the concept of eternity to be applied as an action, making something gain eternal quality.
By eternising moments in photographs and writing, humans are literally defying death—we're fighting against time's ability to erase our experiences, which might be why we love keeping journals and taking pictures.
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