The answer is vocabulary spurt.
The vocabulary spurt, also known as the "naming explosion," typically occurs around 18 to 24 months of age. During this period, children rapidly increase their vocabulary, learning new words at a much faster rate than before.
Gesturing, such as pointing or waving, usually begins around 9 to 12 months of age. It is an important part of early communication and often precedes verbal language development.
Cooing is one of the earliest language milestones and typically occurs around 2 to 3 months of age. It involves making soft, vowel-like sounds and is an early form of vocalization.
Babbling generally starts around 4 to 6 months of age. It involves repeated consonant-vowel combinations, such as "ba-ba" or "da-da," and is a crucial step in the development of speech.
In summary, the vocabulary spurt is achieved last among the listed milestones.