Final answer:
Infants enter the one-word utterances stage of language development typically at about 12 months old, following the babbling phase and preceding the two-word stage.
Step-by-step explanation:
Generally, a child's first word is uttered sometime between the ages of 1 year to 18 months, and for the next few months, the child will remain in the "one word" stage of language development. During this time, children know several words, but they only produce one-word utterances.
The child's early vocabulary is limited to familiar objects or events, often nouns. Although children in this stage only make one-word utterances, these words often carry larger meanings (Fernández & Cairns, 2011). So, for example, a child saying "cookie" could be identifying a cookie or asking for a cookie.
Infants across various cultures enter the one-word utterances stage of language development generally around 12 months of age. This significant milestone marks the beginning of meaningful speech, where a single word often conveys a larger message.
For example, an infant might use the word "cookie" not just to identify it, but perhaps to also express a desire to have one. This stage comes after the babbling phase, where infants start to repeat syllables, and is followed by the two-word stage, happening around 18 months, where they start combining words to form more complex meanings.