Pseudogapping is an ellipsis mechanism that elides most but not all of a non-finite verb phrase; at least one part of the verb phrase remains, which is called the remnant. Pseudogapping occurs in comparative and contrastive contexts, so it appears often after subordinators and coordinators such as if, although, but, than, etc. It is similar to verb phrase ellipsis (VP-ellipsis) insofar as the ellipsis is introduced by an auxiliary verb, and many grammarians take it to be a particular type of VP-ellipsis. The distribution of pseudogapping is more restricted than that of VP-ellipsis, however, and in this regard, it has some traits in common with gapping. But unlike gapping, pseudogapping occurs in English but not in closely related languages. The analysis of pseudogapping can vary greatly depending in part on whether the analysis is based in a phrase structure grammar or a dependency grammar. Pseudogapping was first identified, named, and explored by Stump (1977) and has since been studied in detail by Levin (1986) among others, and now enjoys a firm position in the canon of acknowledged ellipsis mechanisms of English.

In linguistics, gapping is a type of ellipsis that occurs in the non-initial conjuncts of coordinate structures. Gapping usually elides minimally a finite verb and further any non-finite verbs that are present. This material is "gapped" from the non-initial conjuncts of a coordinate structure. Gapping exists in many languages, but by no means in all of them, and gapping has been studied extensively and is therefore one of the more understood ellipsis mechanisms. Stripping is viewed as a particular manifestation of the gapping mechanism where just one remnant appears in the gapped/stripped conjunct.