Made columnar in form; converted into or arranged as columns.
From 'columnar' + the suffix '-ize' (meaning 'to make or become') + '-ed' (past tense). A technical term from materials science and engineering.
The '-ize' suffix is so powerful that you can basically turn any adjective into a verb, so 'columnarized' means 'we made it columnar'—English lets you build almost infinite technical terms once you learn the rules.
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