fox, box, wax
Some singular nouns that end in 'es' are: species glasses clothes series Charles Ramses
nouns ending in -ies = species / series nouns that end in -s = crossroads / barracks / headquarters / means / Swiss
Octopus
Some singular nouns that end with on S are: abacus animus axis bias bonus bus cactus campus census chaos chorus circus debris dais esophagus fetus ficus genius hippopotamus hubris hummus ibis iris...