-abel/'a.bəl/ is a non-native productive suffix found in adjectives based on non-native roots and (occasionally) nouns. The roots in -abel formations are often found in verbs in -eer as well; Smessaert (2013: 98) describes the relation between -abel formations and -eer formations in terms of affix substitution. In the case of a corresponding transitive verb, the meaning of the -abel formation can be described as V-able, able to be V'd, e.g. acceptabelacceptable (cf. accepterento accept); if the verb is intransitive (unergative), the semantics is being able to V, e.g. variabelvariable (cf. variërento vary) Haas (1993: 340). As Haas (1993: 341) point out, -abel derivations corresponding to transitive verbs tend to modify the corresponding direct object (men accepteert de uitslagone accepts the outcome - de uitslag is acceptabelthe outcome is acceptable), whereas -abel derivations corresponding to intransitive verbs tend to modify the subject (de werktijden variërenworking times vary - de werktijden zijn variabelworking times are variable). The suffix can be considered to be the non-native counterpart of native -baar (cf. here).

Occasionally, the suffix attaches to nouns, e.g. professorabelhaving the potential to become a professor (< professor) and ministeriabelhaving the potential to be elected Minister (with the variant iabel).

There is also a variant -ibel/'i.bəl/ found in adjectives such as flexibelflexible and compatibelcompatible.

The suffixes -abel and -ibel are stress-bearing (stress on the first syllable of the suffix) (acceptabel/ɑk.sɛp.'ta.bəl/acceptable, compatibel/kɔm.pa.'ti.bəl/compatible). As the transcriptions show, the affixes are cohering: syllabification does not respect the morphological structure.

Adjectives in -abel show standard adjectival inflection and can be used both attributively (een acceptabele voorstellingan acceptable performance) and predicatively (de voorstelling was acceptabelthe performance was acceptable). Comparative and superlative forms are rare, probably for semantic reasons, but possible (Zwangerschapsduur variabeler dan verwachtlength of pregnancy more variable than expected); nonimalizations with (non-native) -iteit (e.g. acceptabiliteitacceptability.