Pernilla Hallonsten Halling

The word form level

As discussed in chapter 4, an exhaustive analysis and comparison of the encoding found
in attr, pred, and adv in certain languages requires the use of a word form level,
as opposed to a lexeme level. The word form level is relevant when a word form (or affix) occurring as agreement in one function is used also for the purpose of expressing another function. While there is no example in the sample quite like that of Swedish (Indo-European), where one Adjective form (the neuter) appears to be used also to form Adverbs (cf. example 4.6 in section 4.2), Estonian (Uralic) is a candidate for a similar pattern, using ablative case to form Adverbs.
(6.9) Estonian (Uralic) (Bernhard Wälchli, p.c., cited in Loeb-Diehl 2005: 232)¹

tuˇdruk
girl
laulub
sing.3sg.prs
ilusa-lt
beautiful-abl
adv

‘The girl sings beautifully.’
The fact that ablative occurs as a case ending in attr by agreement with the Noun and can form Adverbs in adv would then mean that Estonian has a partial word form overlap of at least attr and adv.
A different overlap of encoding in terms of word form, or at least a candidate for this, is found in Cavineña (Tacanan). Here, a subclass of what Guillaume (2008: 360) calls “Predicative Adjectives” carry the empty suffix -da. In attr, they are used in a relative clause with an optional copula ju-.
(6.10) Cavineña (Tacanan) (Guillaume 2008: 360-361)

1. 
   ...jae=ra
   

fish=erg
tinu-kware
pull-rempst
amena
bm
[wika hook