Nouns ending in x and its plural?

Singular nouns that end in -x add -es to the end of the word to form the plural; for example:

  • ax, axes
  • box, boxes
  • fax, faxes
  • fox, foxes
  • ibex, ibexes
  • suffix, suffixes
  • tax, taxes
  • wax, waxes

Note: All of the above are regular plurals. There some nouns ending in -x that are irregular plurals; for example the plural for ox is oxen, the plural for matrix is matrices (although, matrixes is now becoming accepted).