Words a person uses in talking or writing.

• Active vocabulary

• Passive vocabulary

• Verbal vocabulary

• Silent vocabulary

Infant speech using the tongue and the front of the mouth to make a consonant-vowel sound such as ba.

• Babbling

• Mumbling

• Mouthing

• Stuttering

An idea formed by combining what is known about a person, object, place, quality, or event.

• Imagination

• Thought

• Concept

• Judgement

Light, happy, vowel-like sound babies use to communicate between six and eight weeks after birth.

• Babble

• Coo

• Cry

• Laugh

Ability to tell how car away something is.

• Distance perception

• Depth perception

• Vision clarity

• Zone of proximal development

Ability to understand that objects, people, and events are separate from a person's interactions with them.

• Object constancy

• Object identity

• Object permanence

• Object concept

Ability to understand that objects remain the same even if they appear different.

• Object constancy

• Object concept

• Object identity

• Object permanence

Ability to understand that an object stays the same from one time to the next.

• Object concept

• Object constancy

• Object identity

• Object permanence

Ability to understand that people, objects, and places still exist even when they are no longer seen, felt, or heard.

• Object concept

• Object constancy

• Object identity

• Object permanence

Infant-directed, sing-song, high-pitched style in which parents and other adults speak to babies.

• Parentese

• Baby talk

• Cooing

• Babbling