The one-word stage (also called the holophrastic stage) is the period of language development, roughly 10-18 months, when a child uses single words to express complete thoughts, like saying 'milk' to mean 'I want milk.' It follows babbling and comes before telegraphic speech.
The one-word stage is the point in language development when a toddler starts producing real, meaningful words, one at a time. It usually kicks in around the first birthday (about 10-18 months). The key idea is that one word does the work of a whole sentence. A child who says 'dog' might mean 'Look at the dog,' 'Where's the dog,' or 'The dog took my cracker.' That's why this stage is also called the holophrastic stage, because a single word (a holophrase) carries an entire message.
This stage sits in the middle of a predictable sequence you need to know for Topic 5.11: babbling (around 4 months) → one-word stage (around 12 months) → two-word/telegraphic speech (around 24 months). Kids in this stage also make classic meaning errors. Overextension is stretching a word too far (calling every four-legged animal 'doggy'), and underextension is using a word too narrowly (using 'doggy' only for the family dog). Those errors are evidence that children are actively building word-to-meaning categories, not just imitating sounds.
The one-word stage lives in Topic 5.11, Components of Language and Language Acquisition, in the Cognition unit. The CED expects you to know the components of language (phonemes, morphemes, grammar) and the stages children move through as they acquire it. The one-word stage is your anchor point in that timeline. It's also where the big theoretical debate plays out. Skinner argued language is learned through association, imitation, and reinforcement, while nativist views point to a universal timetable that all children follow regardless of culture. The fact that kids everywhere hit the one-word stage around the same age, and make the same overextension errors with words nobody taught them, is evidence that gets used in that debate.
Keep studying AP Psychology Unit 5
Telegraphic Speech (Unit 5)
Telegraphic speech is the stage that comes next, around age 2, when kids string two words together like 'go car' using mostly nouns and verbs. Think of it as the one-word stage's sequel. Exam questions love asking you to put these stages in order.
Overextension and Underextension (Unit 5)
These are the signature errors of the one-word stage. A toddler with one word for 'dog' applies it to cows and cats (overextension) or refuses to use it for any dog but their own (underextension). Both show the child is forming concepts, which ties language back to the broader cognition content of Unit 5.
B.F. Skinner (Units 3 & 5)
Skinner's behaviorist account says children acquire words by associating sounds with meanings and getting reinforced for correct usage. The one-word stage is where that theory gets tested, since parents clearly reward 'mama,' but kids also produce words and errors no one ever reinforced.
Critical Period (Unit 5)
The predictable timing of the one-word stage supports the idea of a critical (or sensitive) period for language. Children who miss language exposure during these early windows struggle to ever develop full fluency, which is why the stage sequence matters beyond just memorizing ages.
This term shows up mostly in multiple-choice questions about the order and timing of language development stages. A typical stem asks which stage follows babbling and features isolated single words, or gives you a scenario (a 13-month-old saying 'juice!' to request a drink) and asks you to name the stage. You should be able to do three things: place the one-word stage in the correct sequence (babbling → one-word → telegraphic), attach the rough age (around 1 year), and recognize overextension or underextension errors happening within it. No released FRQ has used the term verbatim, but language acquisition concepts are fair game in scenario-based free response, where you'd apply the stage to a described child's behavior rather than just define it.
Both are early speech stages, but the one-word stage (around 12 months) is single words standing in for whole ideas, like 'milk' meaning 'I want milk.' Telegraphic speech (around 24 months) is two-or-more-word combinations stripped down like a telegram, such as 'want milk' or 'go car.' Quick test: count the words. One word means one-word stage; short multi-word phrases with grammar missing means telegraphic.
The one-word stage occurs around 10-18 months, when toddlers use single words to express complete thoughts.
It's also called the holophrastic stage because one word (a holophrase) carries the meaning of an entire sentence.
The stage sequence to memorize is babbling, then the one-word stage, then telegraphic (two-word) speech around age 2.
Overextension (calling all animals 'doggy') and underextension (using 'doggy' for only one dog) are the classic errors of this stage.
The universal timing of the one-word stage across cultures is used as evidence in the nature-versus-nurture debate over language, with Skinner on the learning side.
It's the stage of language development, around 10-18 months, when a child uses single words to communicate whole ideas, like saying 'up' to mean 'pick me up.' It falls between babbling and telegraphic speech in the language acquisition timeline for Topic 5.11.
Yes, they're the same thing. 'Holophrastic' just means a single word (a holophrase) carries the meaning of a full phrase or sentence. Either name can appear on the exam.
The one-word stage (around age 1) is single words only. Telegraphic speech (around age 2) is short multi-word combos like 'go car' that keep nouns and verbs but drop grammar words. If a question shows two or more words strung together, it's telegraphic, not one-word.
No. Babbling, which starts around 4 months, is just sound play (ba-ba-ba) with no attached meaning. First real words with meaning mark the start of the one-word stage, around 12 months.
That's overextension, a normal error of the one-word stage where a child stretches one word to cover an entire category. The opposite error, underextension, is using a word too narrowly. Both are common MCQ scenarios in Topic 5.11.
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