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In linguistics, reconstructions are words that are not directly attested in any known written work, but which have been hypothetically recreated through analysis of related words which are attested. These words are essential aspects of the analysis of the development of language, and especially ancient languages. However, because of their speculative nature, they are often disputed or disputable, so only reconstructed forms with wide support and/or usage should have their own entries.

As a matter of convention, all reconstructed words are denoted by an asterisk (*) placed at the beginning of the form. This helps keep hypothetical forms distinct from actual words known to exist in languages (e.g., it keeps ad- and *ad- separate), and makes it immediately clear when a form is a reconstruction. All entries in this category, therefore, should begin with an asterisk.