Of or pertaining to aldermen or their office; relating to aldermanic governance (more elaborate form of aldermanic).
From alderman + -ical (double suffix: -ic + -al), an intensive or more formal variant of aldermanic, suggesting greater emphasis on the aldermanic nature of something.
The difference between 'aldermanic' and 'aldermanical' shows how English stacks suffixes for emphasis—one is official, the other is almost comically formal and pompous.
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