Click sounds are short, crisp noises that are made through rapid motions of the tongue, lips, or other parts of the mouth. They are common in many languages around the world and serve different linguistic functions depending on the language. In English, click sounds are not phonemic, meaning they do not change the meaning of words. However, in some languages like Xhosa and Zulu, clicks are an integral part of the phonetic system.
Types of Click Sounds
There are several main types of click sounds that are distinguished by where they are produced in the mouth:
Bilabial Clicks
Bilabial clicks are produced by rapidly sucking in air between the two lips. They make a popping sound written as “ʘ” in the International Phonetic Alphabet. These types of clicks are found in languages like Sandawe, Hadza, and Khoisan.
Dental Clicks
Dental clicks involve placing the tongue on the back of the upper teeth and sharply sucking in air. They make a sharper clicking noise written as “!” in IPA. These clicks are found in many Bantu languages like Zulu, Xhosa, and Ndebele.
Alveolar Clicks
Alveolar clicks are produced by sucking air with the front of the tongue at the alveolar ridge. They make a clicking sound written as “!” in IPA. These types of clicks are found in languages like Juǀʼhoansi and Ekoka ǃKung.
Palatal Clicks
Palatal clicks involve placing the front of the tongue on the hard palate and making a sucking sound. They produce a clicking noise written as “ǂ” in IPA. These clicks occur in languages of southern Africa like Xhosa, Zulu, and Sesotho.
Lateral Clicks
Lateral clicks are made by putting the tongue on the side teeth and roof of the mouth. Air is sucked in to produce a hollow popping sound written as “ǁ” in IPA. They are found in languages like Xhosa, Zulu, and Ekoka ǃKung.
Functions of Clicks
Clicks serve a variety of linguistic functions depending on the language. Here are some of the main uses of clicks in languages:
Phonemic Contrasts
In many Khoisan and Bantu languages of southern Africa, clicks function phonemically to distinguish words. For example, in Xhosa, “uxolo” with a dental click means “peace” while “utholo” with an alveolar click means “well-being.” Clicks make minimal pair contrasts between words.
Word Roots
Some languages like Zulu and Xhosa use clicks as integral parts of word roots and stems. For example, in Zulu, “ngeke” means “never” while “ngeǃeke” with a palatal click means “solemn promise.” Clicks form core parts of words.
Grammatical Markers
Clicks can also function as grammatical markers to show parts of speech and modifiers. In Xhosa, the alveolar click “!” can be added to nouns to change them to diminutives. For example, “umntwana” means “child” while “umntwanana!” means “little child.”
Interjections
Clicks are commonly used as interjections to express concepts like approval, disapproval, or getting an animal’s attention. In many Bantu languages, the alveolar click “!” can mean “tsk tsk” to show disapproval while the lateral click “ǁ” expresses approval.
Deictics
Some languages utilize clicks as deictics or pointers to refer to specific objects, places, or people. In Xhosa, the lateral click “ǁ” plus a noun can mean “this/that” to specify something contextually. For example, “ǁumntwana” means “this child.”
English Click Sounds
While clicks do not change word meaning in English, they are used in several forms of non-lexical communication:
Disapproval
English speakers express disapproval or impatience by sucking in air using the tongue and teeth, producing an alveolar click sound “!.” This functions similarly to sounds like “tut tut.”
Getting Attention
To get someone’s attention, an English speaker may make a lateral or alveolar click sound. This is often written as “tsk” in English orthography to represent the clicking noise.
Urging on Animals
Clicking the tongue against the roof of the mouth is used to urge on horses and other animals. The lateral click “ǁ” is often used for this purpose in English.
Imitative Sounds
English speakers may use clicks to imitate or replicate non-verbal sounds. For example, the alveolar click “!” can mimic the sound of a bottle being opened.
| Click Type | IPA Symbol | Languages |
|---|---|---|
| Bilabial click | ʘ | Sandawe, Hadza, Khoisan |
| Dental click | ! | Zulu, Xhosa, Ndebele |
| Alveolar click | ! | Juǀʼhoansi, Ekoka ǃKung |
| Palatal click | ǂ | Xhosa, Zulu, Sesotho |
| Lateral click | ǁ | Xhosa, Zulu, Ekoka ǃKung |
Click Consonant Inventories
The number of click phonemes varies significantly across the southern African languages that utilize them. Here are some examples of click consonant inventories:
- Hadza – One bilabial click /ʘ/
- Sandawe – Two bilabial clicks /ʘ/ and /ɡʘ/
- Juǀʼhoansi – 15 clicks including bilabial, dental, and lateral varieties
- Xhosa – 18 clicks including two kinds of bilabial, dental, alveolar, palatal, and lateral clicks
- Zulu – At least 20 documented clicks
Clicks almost always occur in combination with other pulmonic consonants. In Xhosa, Zulu, and other Bantu languages, clicks appear at the beginning of syllables and are followed by vowels like a, e, i, o u. Some examples of click consonant combinations in Xhosa include:
- c̪hǀha – /ɡǀh/ – cheek
- iɣǁadi – /iɣǁadi/ – lightning
- inkǂenkǂenkǂe – /inkǂenkǂenkǂe/ – type of beetle
Click Acquisition
Clicks are difficult sounds for adult language learners to master, but infants generally acquire clicks in their native languages easily by age 1. Some key facts about click acquisition include:
- Clicks are produced reflexively by infants as they learn to eat and explore their mouth.
- Infants babbling click sounds between 2-6 months as they practice speech.
- Clicks emerge in first words around age 1, showing mastery.
- Adults struggle with click production; clicks require precision and practice.
- Second language clicks remain difficult due to interference from earlier phonetic learning.
While clicks do not convey lexical meaning in English, parents may notice infants spontaneously producing click sounds as part of the typical process of exploring sounds. English-acquiring babies will produce clicks, but eventually cease as clicks carry no communicative significance in English.
Perception of Clicks
Research has shown that people struggle to differentiate click contrasts they did not acquire as children. Here are some key findings regarding click perception:
- English speakers cannot easily distinguish dental vs. lateral clicks.
- Xhosa speakers perceive Xhosa clicks categorically as phonemically contrastive.
- Xhosa speakers also struggle with click distinctions not used phonemically in their language.
- Click perception adapts to native click inventory and wanes for non-native clicks.
- Infants lose ability to universal click perception if clicks are not phonemic in native language.
This research shows that our click perception becomes tuned to the phonemic click distinctions used in our native languages. While infants are universally sensitive to all click contrasts, language-specific listening emerges by the first year of life.
Neurology of Clicks
Producing the precise articulations required for clicks involves some unique neurological adaptations not found in most languages. Research has shown:
- Clicks require very fast, complex articulatory maneuvers of the tongue.
- This rapid movement is enabled by synched firing of the trigeminal nerve.
- The trigeminal nerve innervates the face muscles controlling tongue and mouth.
- Precise coordination of trigeminal nerve firing allows click production.
- This neuromotor control is established in infancy as clicks are acquired.
The trigeminal nerve plays a key role in enabling the motor skills needed to produce clicks. Adult learners of click languages often struggle with this aspect of production.
Click Loss
While clicks remain widely used in languages of southern Africa today, some languages have lost clicks over time. For example:
- Proto-Bantu reconstructed with 4 click consonants.
- Swahili and Zulu retain 2 of these ancestral clicks.
- Swahili uses clicks for loanwords but no native words.
- Sesotho lost clicks completely, becoming a non-click language.
- Language contact with non-click languages can contribute to click loss.
Scholars hypothesize several possible drivers of click loss in languages over time, including:
- Greater linguistic complexity of large click inventories.
- Difficulty of click acquisition for second language learners.
- Prestige and dominance of non-click languages.
- Erosion of clicks in casual speech.
- Cultural association of clicks with colonial marginalization.
The presence or absence of clicks has no bearing on a language’s expressiveness – clickless languages like Swahili and Sesotho are perfectly functional and expressive. However, clicks remain integral to many southern African identities.
Conclusion
Clicks comprise a unique and specialized class of consonants distinct from pulmonic sounds. They have evolved for thousands of years in southern African languages to become integral parts of their phonologies. Clicks enable concise and differentiated lexicons, convey grammatical information, and express social meanings in these languages. Adult English speakers may struggle to produce clicks, but they occur reflexively in infants. Clicks represent one of many ways that the ingenuity of human languages has expanded our phonetic repertoire.
