While considered an isolate, there have been attempts to connect Atakapa with other languages of the Southeast. In 1919 John R. Swanton proposed a Tunican language family that would include Atakapa, Tunica, and Chitimacha; Morris Swadesh would later provide work focusing on connections between Atakapa and Chitimacha. Mary Haas later expanded the proposal by adding Natchez and the Muskogean languages, a hypothesis known as Gulf. These proposed families have not been proven. The similarities between Atakapa and Chitimacha, at least, may be attributable to periods of "intense contact owing to their geographic proximity."
Geographical variation
According to Swanton and Goddard, Atakapa could be classified into Eastern and Western varieties. Eastern Atakapa is known from a French-Atakapa glossary with 287 entries, compiled in 1802 by Martin Duralde. The speakers interviewed by Duralde lived in the easternmost part of Atakapa territory, around Poste des Attakapas, now Franklin, Louisiana. Western Atakapa is the better-attested of the two varieties. In 1885, Albert Gatschet collected words, sentences, and texts from two native Atakapa-speakers, Louison Huntington, and Delilah Moss at Lake Charles, Louisiana. John R. Swanton worked with another two speakers near Lake Charles: Teet Verdine in 1907, and Armojean Reon in 1908. Additionally, in 1721, Jean Béranger collected a small vocabulary from captive speakers in Galveston Bay. John Swanton argued that the Béranger vocabulary represented the Akokisa language, spoken by a people who lived somewhat inland from Galveston Bay. There is little evidence to support his assertion.
Phonology
Vowels
Atakapa has five vowels as presented in Swadesh. Vowel length is not contrastive in Atakapa.
Front
Central
Back
Close
i
u
Mid
e
o
Open
a
Consonants
According to Swadesh, Atakapa has the consonants presented in the following chart.
Labial
Dental
Alveolar
Palatal
Velar
Glottal
Plosive
p
t
c
k
Nasal
m
n
ŋ
Fricative
ł
š
h
Approximant
w
l
y
Underlying /ŋ/ surfaces as when it appears at the end of a syllable. Swadesh further notes that /m/ often surfaces as or word-finally in some adjectives, but "irregular variations in writing" preclude him from settling on any further conditions for this. Additionally, it is unclear whether /n/ is indeed a distinct phoneme from /ŋ/; if this is the case, argues Swadesh, then words containing final /n/ must have arrived in a later period. Consonant clustersconsisting of a stop followed by a sibilant — themselves arising from vowel epenthesis — are generally contracted to /c/. For example, kec-k arose from *keks, which arose from epenthesis and final-vowel deletion processes in *kekesi, which itself is the reduplicated form of *kesi. However, there are words in which the suffix -kš appears, suggesting that this contraction rule ran its course in an earlier period.
Syllable structure and stress
The typical Atakapa syllable is of the structure CVC. Swanton observes that clusters of more than two consonants are rare in the language. From his analysis of Gatschet's data, he concludes that consonant clusters of any size are not permitted in the syllable onset, but that they are permitted in the coda. Stress is "a purely mechanical function of phrase rhythm" in Atakapa; it is generally the final syllable of a phrase that receives stress.
Morphology
The Atakapa language is a mostly agglutinative, somewhat polysynthetic language of the templatic type. This meaning that the language stacks a number of affixes to express locatives, tense, aspect, modality, valency adjustment, and person/number, which are assembled in a rather specific order. Person marking is one of the only instances of fusion within the language, fusing both person and number. Nouns have only a handful of suffixes and usually take only one suffix at a time. The language is largely head-marking; however, reduplication of an adjectival stem tends to show dependent-marking, as it often expresses the plurality of the noun it describes.
shāk tōl "good man"
shāk tōltōl "good men"
Pronominal morphology
Object pronouns are prefixed to verbs, while subject pronouns are suffixed. There are independent forms of each pronoun as well: in the first person singular and plural, this form appears to be distinct from either affix, but in the second and third persons, the affixes seem to be related to the independent forms. Grammatical gender appears not to occur in Atakapa, though evidence for it in nearby languages has been found. The following table of pronominal forms is presented in Swanton.
Number
Person
Independent
Objective
Subjective
Singular
1
wi
hi-
-ō
Singular
2
na
na-, n-
Singular
3
ha
ha-
Singular
Indefinite
hi-
Plural
1
yūkit
ic-
-tse
Plural
2
nakit
nak-
-tem
Plural
3
hakit
hak-
-ūl, -ti
In addition, Swanton notes the existence of a reflexive prefix hat- and a reciprocal prefix hak-. However, the reflexive form may be a circumfix rather than a prefix: Kaufman cites the example of hat-yul-šo, in which both hat- and -šo indicate reflexivity.
Nominal morphology
There are multiple ways to indicate a noun's plurality in Atakapa:
attachment to the noun of the suffix -heu
attachment to the noun of the prefix -šak
reduplication of the accompanying adjective
employment of the plural suffix in the accompanying adjective and/or verb
According to Swanton, a noun-forming affix -nen or -nan exists in Atakapa.
Verbal morphology
The full order of morphemes within the verb complex is:
It is unclear whether or not a distinct class of auxiliary verbs exists in Atakapa; the difference between a stem-plus-auxiliary construction and a two-verb-serialization construction is not well marked. Additionally, there is no mention of the assertive suffix -š in Swanton's work; Kaufman derives it by analogizing Atakapa and Chitimacha.
Verb serialization
is a productive process in Atakapa.
pam-nima : beat to death.
ta-wat-ten : pray.
Syntax
Atakapa exhibits strict subject-object-verb word order. While verbs are typically found in sentence-final position, it is common for adjuncts, or even subordinate clauses, to follow the verb of the principal clause. The suffixes -ne and -n are used to indicate the subordination of a clause to the main clause, as in tsanuk micat penene. With occasional exceptions, adjectives follow the nouns they describe. Adverbs follow nouns and adjectives, but precede verbs.
Case marking
Atakapa marks only the locative case. The language has four locative suffixes, in addition to a series of locative postpositions. These suffixes and postpositions may be placed after nouns, adjectives, and demonstratives.
-kin, the most frequently-occurring suffix, expresses the sense of English "in" or "on," as in nun-kin tōhulāt.
* -ki occurs in similar contexts.
-ip corresponds roughly to English "at," and is very commonly used with nē, "down," to form nēp, "below."
-ik generally parallels English "with," as in hatyūlcō nōhik.
Noun incorporation
Swanton asserts that noun incorporation is present in Atakapa, but he provides no examples of this.
Deixis
Three demonstratives serve as deictics in Atakapa:
