Navajo is an Athapaskan language, belonging to the Na-Dene phylum. It is like the Apachean languages in that although the majority of the languages in the Na-Dene family are spoken much farther north (Alaska, Yukon, Northwest Territories, and Canadian Provinces) Navajo is spoken much farther south (in the southwest United States) by the Navajo people. Navajo claims more speakers than any other Native American language north of the Mexican border, with more than 100,000 native speakers, and this number is actually increasing with time. During World War II, a code based on Navajo was used by code talkers to send secure military messages over radio.

Typologically, Navajo is an agglutinative language, but many of its affixes combine into barely recognizable contractions. Navajo words are altered primarily by prefixes, with circumfixes playing some part as well. The key element in Navajo is the verb, with even some noun meanings provided by verbs; many complex nouns are derived from verbs as well; for instance, the Navajo word łéé'íí'nííł "cemetery" is actually a verb meaning "they lie in the ground". Navajo has a large variety of noun classes including "animate", "round object", "long, stiff object" and "granular object". Many basic verbs in Navajo may translate into many words in English; for instance, the verb si' means "to cause a hafted [better def.?] object to move" or, more practically, "to practise archery".

There are four phonemic vowels in Navajo: a, e, i and o; each of these may occur long, nasalized, or with one of four tones: high, low, rising or falling. Various combinations of these features are also possible.

The consonants of Navajo are:

 Bilabial       b        m  'm
 Alveolar       d  t  t' n  'n
 Prepalatal     g  k  k' 
   labialised      kw
 Palatal                        y      'y
 Postpalatal                    gh  x
   labialised                   ghw xw
 Sibilant    
   alveolar                     z   s     dz  ts  ts' 
   postalveolar                 j   c     dj  tc  tc' 
 Lateral                        l1  lh    dl  tl  tl' 
 Glottal           '                h/x

Or, in SAMPA-style notation:

		bilabial	alveolar	(alveolar) lateral	(alveo-) palatal	velar	labialized velar	glottal
stop	unaspirated	p	t	&nbsp	&nbsp	k	kw	’
	aspirated	&nbsp	th	&nbsp	&nbsp	kh	&nbsp	&nbsp
	ejective	&nbsp	t’	&nbsp	&nbsp	k’	&nbsp	&nbsp
affricate	voiced2	&nbsp	dz	dl\	dZ	&nbsp	&nbsp	&nbsp
	voiceless	&nbsp	ts	tl\	tS	&nbsp	&nbsp	&nbsp
	ejective	&nbsp	ts’	tl\’	tS’	&nbsp	&nbsp	&nbsp
fricative	voiced	&nbsp	z	&nbsp	Z	G	Gw	&nbsp
	voiceless	&nbsp	s	l\³	S	x	xw	h&nbsp
liquid	voiced	&nbsp	&nbsp	l	j	&nbsp	&nbsp	&nbsp
	preglottalized	&nbsp	&nbsp	&nbsp	’j	&nbsp	&nbsp	&nbsp
nasal	voiced	m	n	&nbsp	&nbsp	&nbsp	&nbsp	&nbsp
	preglottalized	’m	’n	&nbsp	&nbsp	&nbsp	&nbsp	&nbsp

1. The lateral approximant l is treated as part of an overall lateral class in some Navajo grammars; however, it is the only approximant in the class, all other lateral phonemes being based on voiced and voiceless lateral fricatives instead. Some Athabaskan languages, notably Han, have no voiced lateral approximant, distinguishing only a voiced and voiceless lateral fricative.

2. The standard orthography uses English voiced stop symbols for the unaspirated phonemes, as in rapid speech these are frequently heard as voiced. It is also unclear from the orthography whether the affricates use a voicing or aspiration contrast.

3. Note that the first chart fails to clearly distinguish liquids and fricatives; in particular, it is unclear whether lh is a voiceless lateral liquid or a voiceless lateral fricative.

As in many northwestern American languages, Navajo is extremely poor in labial consonants.

See also: Languages in the United States

Wikipedia in Navajo: here .