A Raritätenkabinett (cabinet of rarities) is a collection of things, living or dead, which are considered worth collecting (and perhaps exhibiting) because they are rare. An online collection of grammatical rarities is available at https://typo.uni-konstanz.de/rara/
The site classifies the items it contains into the following categories:
- rarum (plural rara): ‘a trait (of any conceivable sort: a form, a relationship between forms, a matching of form and meaning, a category, a construction, a rule, a constraint, a relationship between rules or constraints, …) which is so uncommon across languages as not even to occur in all members of a single (middle to lower level) family or diffusion area (for short: sprachbund), although it may occur in a few languages from a few different families or sprachbünde’.
- rarissimum: even rarer than a rarum
- singulare (or nonesuch): unique to individual languages.
The site emphasises that claims of rarumhood, rarissimumhood, and nonesuchhood are only tentative at this stage, and subject to revision.
When I looked in the cabinet today, it contained 148 items. I list a few below, for English and for other languages. I have added comments if I think readers may not understand the description.
Rarities in English
The site lists the following for (modern standard) English:
- rarissimum 34: verb inflection with non-zero exponent for 3rd person (subject or object agreement/cross-reference), but zero for all other persons
Comment: this is the distinction between makes (3rd person singular) and make (all other persons)
- rarissimum 70: independent personal pronouns for 1st and 3rd (animate) person inflecting for both number and case, but that for 2nd person inflecting for neither category (defectiveness of 2nd person pronouns in number alone being more common)
Comment: the contrast is between I/we, he/she/they and you
- rarissimum 81: (finite) verb-second word order in main declarative clauses only if the first constituent is an adverbial with strong negative force (such as never before, hardly ever)
Comment: example—’never before had she done this’.
- rarissimum 84: relative pronoun as the only target for agreement in animacy
Comment: I think this is talking about the contrast between who and what.
- rarissimum 122: a definite article [the] formally distinct from (one form or another of) any kind of pronoun – demonstrative, personal (free, clitic, or bound), possessive, relative, interrogative
Rarities in other languages
Some other items
- rarissimum 8: laminal (tongue-blade) trill.
In Czech (Slavonic, Indo-European)
Comment: this is the sound represented by ř in the name of the composer Dvořak.
- rarissimum 143: only a single adjective – that is, one item of a word class distinct from other word classes (in particular nouns and verbs) and comparable to a word class of adjectives in other languages.
In Toqabaqita (Austronesian, spoken in the Solomon Islands)
- rarum (or infrequentale?) 131: a phoneme inventory with more vowels than consonants (10: 8).
In Hawaiian, and probably other Polynesian languages (Austronesian)
- nonesuch 132: a phoneme inventory with almost 40 times as many consonants as vowels.
In Ubykh (Northwest Caucasian)
- nonesuch 116: different definite article depending on whether an accompanying adjective denotes colour or another kind of property concept.
In Belhare (Kiranti, Tibeto-Burman)
- rarissimum 69: a quadral number with personal pronouns.
In Sursurunga, Tangga (both Patpatar-Tolai, Austronesian) (?)
Comment: Some languages distinguish singular from plural. A few distinguish singular from dual (2) from (other) plural. Fewer still distinguish singular from dual (2) from trial (3) from (other) plural. And this one adds a further distinction: quadral (4).
- rarissimum (or infrequentale?) 133: ‘eight’ as regular base for a numeral system.
In Pamean languages, especially Northern Pame (Otomanguean)
The same site also contains a Universals Archive. This is a Database complied at the University of Konstanz (Germany) as a result of a project to collect and document linguistic universals. The universals are ones that have been suggested in the relevant literature, particularly those of an implicational kind (“If a language has property [unit, category, rule, construction, pattern, …] X, then it will also have Y”).
Here are a few of the (many) universals listed:
- Universal 469: IF long consonants occur in non-intervocalic position, THEN they will occur in intervocalic position.
- Universal 789: IF there are only two Primary Nasal Consonants, THEN the first one is apical (/n/), and the other is /m/, that is its most characteristic allophone is labial.
- Universal 802: back consonant ⇒ front consonant. IF there are back consonants, THEN there will be front consonants.
- Universal 58: IF the general rule is that the descriptive adjective follows the noun, THEN there may be a minority of adjectives which usually precede, but IF the general rule is that descriptive adjectives precede the noun, THEN there are no exceptions.
- Universal 677: IF relative pronouns of interrogative form are used in ad-relative clauses, THEN interrogative pronouns are placed in initial position in questions.
- Universal 1394: All languages have non-reduced adverbial constructions.
If a language has reduced adverbials, these are always more restricted in their privileges of occurrence than non-reduced adverbials.
The universals archive also lists any known counter-examples to each proposed universal.