Where derivations with the suffix -er refer to the agent of a verb, it is rather the verb's patient or theme that is referred to by -sel. The suffix also exists in Dutch, German and the Scandinavian languages. Derivations are object names, with the exception of skepselcreature, which can denote a person. All derived words have neuter gender, although stiselstarch and spruselbit, scrap shifted to the common nouns; for more background, see gender change by opacity of a suffix.

Most words ending in -sel are derived from transitive verbs. They denote the result of the action as described by the verb:

These derivations can both refer to a concrete (cf. bakselbaking) or an abstract entity (cf. betinkselinvention).

Some intransitive verbs may also be the origin of derivations with -sel, and hence it seems as if -sel may also derive subject names:

To be more precise, these intransitive base verbs can be characterized as ergative. This results in a common feature with the transitive verbs above, i.e. that the derivation with -sel refers to a Theme role.

The nouns derived from ergative verbs can be quite abstract, and then the relation with the verb may be relatively far-fetched. Examples are ferskynsel or oerbliuwsel above.

The semantic contribution of the suffix can be characterized as 'product or result of the action denoted by the verb'. For example, bakselbaking is the result of the action of the transitive verb bakketo bake. In a way, this can be transferred to ergative verbs. The result of a verb like bloeieto bloom is bloeiselblossom. The focus on result has the effect that we also find derivations which do not directly reflect the direct object of the verb, but are rather a result or product in a somewhat wider sense. For example, neukselsperm can be a result of the action denoted by the verb neuketo fuck, but the concept of 'sperm' cannot act as the direct object of this verb. Other derivations in the same vein are slypselgrind(ings) (from slypjeto grind), mingselmix (from mingeto mix) or skraabselscrapings (from skraabjeto scrape).

In addition, some derivations with -sel fulfill the role of instrument. Here are some examples:

For example, one cannot execute the action of the verb smarreto spread with a smarselointment as a result. Rather, one needs the result of the derivation smarsel (the object, material) to execute the action of the verb: one needs ointment in order to spread, one needs carbon black in order to blacken, etcetera.

Quite some derivations can have a pejorative character, as is illustrated in the following examples:

In this pejorative use the suffix is particularly productive.

The suffix -sel bears no stress, since it is pronounced with a schwa: [səl]. A phonological restriction is the condition that the stem of the base verb may not end in [s] or [z]. For example, from sketseto sketch one cannot derive *sketsselsketch and a verb like lêzeto read can not be the basis foar *lêssel. The restriction does not apply to gearmjukselhotchpotch, coming from the verb gearmjuksjeto mix. As a second restriction, the base verb may not end in a syllable with a schwa, for instance *teken-sel < teken-jeto draw or *timmersel from the verb timmerjeto hammer.

Suffixation with -sel may result both in mass nouns and count nouns. The latter can regularly be pluralized with the suffix -s, for example betinkselinvention > betinkselsinventions. Many count nouns also have a diminutive form (cf. -DIM). Examples are skepselcreature > skepseltsjesmall creature or smarselointment > smarseltsjeointment.