What is conversion?

Morphologists have been divided on how to analyze conversion. Some argue that conversion is just like affixation, except that the affix is phonologically null – that is, it is unpronounced. When analyzed this way, conversion is called zero-affixation. It might be represented structurally as in (33):

Other morphologists argue that conversion is different from affixation, and treat it simply as change of category with no accompanying change of form, as we have done here. With this analysis, converted verbs like to chair would not have any internal structure, but would simply be regarded as having been relisted or recategorized in our mental lexicons. We will not decide between these analyses here.