In his attempt to formulate the signatum as well as signans parameters for what he calls "extragrammatical formations," Wolfgang Dressier (2005) proposes five (Peircean) semiotic sign-based parameters, including the parameters of iconicity, indexicality, (morphosemantic /morphotactic) transparency, biuniqueness, and figure/ground (see also Mattiello 2013, for a discussion of "extragrammatical" formations).
Indeed, the parameter which applies in this case is based on the so-called biuniqueness principle--the requirement that there should be a one-to-one relation between the signans and the signatum.
The fact that discrete articulations, or phones (as linguists call them), can be mapped onto more than one phoneme in a given language has long been recognized as a problem in phonemic theory, known as biuniqueness
Function-argument biuniqueness solves the uncertainty, mapping the patient onto an object.
The other well-formedness condition, argument-function biuniqueness, enters the constraint set as UNIQ.
37), but the form in which it has come down to us is hardly close to speech, and the extent to which Wulfila created his orthography along the principle of biuniqueness
is open to considerable debate in the light of the manuscript tradition and dialect disparity.
In syntax-centred GB theory, nevertheless, the lexical-semantic properties of predicates in themselves have not been the main focus of interest and the view of th-roles stemming from Lectures (Chomsky 1981) is what Dowty (1991) has called the Argument Indexing Approach demanded by the Thematic Criterion (Th-Criterion), which imposes a condition of biuniqueness
(a one-to-one relation) between arguments and th-roles.
From a pragmatic and sociolinguistic point of view, these can be accepted as marginal members of the category of evaluative morphology, if we take into consideration the biuniqueness
of the sign and the avoidance of synonymy strategy operating in linguistic ecology.
Thus, while biuniqueness, transparency and "constructional iconicity" are certainly iconic, violations of these principles can themselves be iconic in more complex ways.
Dressler (1995: 35, note 1) says that biuniqueness "is related to, but not identical with, the parameter of iconicity.
A good classification should try to account for properties of the entities it classifies preserving their biuniqueness
(pairing of meaning and form) and accommodate their semantic characteristics, related to the peculiarities of the compound family, which is easily achievable in a constructionist framework.
This phase is characterised by morphotactic and morphosemantic transparency, biuniqueness
and constructional iconicity.