Glossary

arbitrary

or arbitrariness, no clear similarity between the form of a construction and its meaning, for example, the word ‘dog’ itself does not have dog-like qualities (cf. iconicity).

common ground

a shared set of social, cognitive and linguistic assumptions between speakers.

consonants

sounds that are relatively more obstructed by the vocal tract than vowels, where the breath escapes suddenly or with friction. Rotokas, spoken in Papua New Guinea has as few as 6 while !Xóõ, with modern-day speakers in Botswana, has around 77.

conventional gestures

an arbitrary pairing between the form of the gesture and its meaning, for example waving goodbye (cf. iconic gestures).

co-speech gestures

movements of the hands, arms, head and body that are integrated with speech.

iconic gestures

are used to communicate something ‘like this’ by pantomiming the action (cf. conventional gestures).

imitation

a form of social learning where individuals observe and replicate the form of others’ behaviour

joint attention

a physical or cognitive space of mutual focus, defined by communicative cues (e.g., eye gaze, pointing, language).

perceptual narrowing

a process of specialisation that occurs when the infant becomes attuned to aspects of their environment they regularly experience and progressively insensitive to those they do not.

prosody

describes the patterns of stress, intonation and rhythm of language that are spread over syllables and phrases. Prosodic information can indicate the emotion or attitude a speaker has to an utterance (e.g., worried, sarcastic, questioning) as well as information about individual words and phrases (e.g., REcord as a noun vs reCORD as a verb). Prosody is often encoded in signed languages by postures or movements of the body, head and face.

proto-conversations

pre-linguistic turn-taking between caregiver and infant characterised by a back-and-forth of synchronised vocalisations, mirroring of behaviour and sharing emotion.

turn-taking

is a basic feature of conversation whereby partners coordinate their contributions in a back-and-forth manner to minimise silence and overlap in speech.

vowels

sounds that typically pass through the vocal tract relatively unobstructed compared to consonants. Ubyx, once spoken around Turkey, had as few as 2 vowels while !Xóõ, with modern-day speakers in Botswana, has around 31.