- In <em>mathematics</em>, the process of obtaining the domain <bt>Ω</bt> from the domain <bt>Ω</bt> by adding to it the number <em>a</em> which does not already belong to it, and adding also all numbers arising from a finite number of additions, subtractions, multiplications, and divisions involving <em>a</em> and all numbers in the domain <bt>Ω</bt>. See the extract.
- The act of joining; the state of being joined. The thing joined.
- In <em>civil law</em>, the joining of one person's property to that of another permanently, as the building of a house upon another's land, painting of a picture on another's canvas, and the like.
- The act of joining; the thing joined or added.
- The act of <xref>joining</xref>; the thing joined or added.
- A form of similarity between a pair of <xref>categories</xref> mapped to each other by <xref>dual</xref> <xref>morphisms</xref>.
- an act of joining or adjoining things