[This is part of a small but growing series of defectivity case studies.]

Icelandic is not the only Scandinavian language to exhibit defectivity in imperatives: Rice (2003, 2004; henceforth R) describes a superficially similar pattern of defectivity in Norwegian adjectives.

In Norwegian, the infinitival form of most verbs consists of the particle å, the verb stem, and a schwa (which, like in German, is spelled -e). Such verbs’ imperatives then consists of the bare stem, without a particle or the schwa; e.g., å skrive ‘to write’/skriv ‘write!’. A second, smaller class of verbs are monosyllables ending in a (non-schwa) vowel. These verbs use the bare verb stem in both infinitive and imperative; e.g., å tre ‘to step’/tre ‘step!’. While R does not go into any details about how these two patterns might be encoded, one might posit two allomorphs of the infinitive suffix, -e and zero. Presumably this allomorphy is in part lexically conditioned, since it seems necessary to distinguish between minimal pairs like å vie ‘to dedicate’/vi ‘dedicate!’, which belongs to the former class, and å si ‘to say’/si ‘say!’, which belongs to the latter. However, R only gives a few examples of vowel-final monosyllable with infinitive in -e (all other verbs of this shape have zero infinitives), so it’s possible these are just exceptions and the allomorphy conditioning is mostly phonological.

A third class of verbs are those whose stem ends in a rising-sonority consonant cluster; e.g., åpne ‘to open’, sykle ‘to bike’.¹ These superficially resemble the first class of verbs (e.g., å skrive) in that they end in a schwa in the infinitive. However, Norwegian does not permit rising sonority codas, so the expected *åpn, *sykl, and so on are ill-formed.

According to R, some speakers simply use circumlocutions to avoid the imperative of such verbs, making this a standard case of defectivity. However, R mentions several other strategies used by Norwegian speakers:²

• The word-final sonorant can be made syllabic (e.g., [oːpn̩]).
• If the cluster consists of a voiceless consonant followed by a sonorant, the sonorant can be devoiced, reducing the sonority rise (e.g., [oːpn̥]).
• One can insert a schwa to break up the cluster (e.g., [oːp.pɘn]).
• One can insert a schwa after the cluster (e.g., [oːp.nɘ]).

One question that arises is whether there are any other places in the Norwegian grammar where we would expect word-final rising sonority consonant clusters to surface. As others have noted (e.g., Albright 2009), most if not all instances of inflectional defectivity are limited to specific morphological categories. For speakers who cannot generate an imperative of verbs like åpne or sykle, is this defectivity limited to this the category of imperatives, or is it found anywhere else in the language?

Endnotes

1. R gives the infinitives of this third class of verbs without the å particle. It is unclear to me whether this is intentional or just an oversight.
2. These forms are ones I have posited on the basis of R’s description, which is not as detailed as one might like.

References

Albright, A. 2009. Lexical and morphological conditioning of paradigm gaps. In C. Rice and S. Blaho (ed.), When Nothing Wins: Modeling Ungrammaticality in OT, pages 117-164. Equinox.
Rice, C. 2003. Dialectal variation in Norwegian imperatives. Nordlyd 31: 372-384.
Rice, C. 2005. Optimal gaps in optimal paradigms. Catalan Journal of Linguistics 4: 155-170.