What is an intraverbal in ABA?
An intraverbal is the verbal operant of responding to language with language - answering questions, completing phrases, and holding conversation, where the response does not echo the words that occasioned it.
When someone asks 'What do you eat?' and the learner answers 'apples', the answer is controlled entirely by the words heard, not by any apple in sight - and it doesn't repeat them. That is the intraverbal: verbal behavior occasioned by someone else's verbal behavior, with no point-to-point match.
Intraverbals are typically the latest-developing operant in early language programs because they lean on everything else. Fill-ins ('Ready, set, ...'), song completions, and animal sounds come first; wh- questions follow; and from there the repertoire grows toward the genuinely hard skills - answering questions about past events, describing things not present, and sustaining back-and-forth conversation.
The operant distinction earns its keep here more than anywhere. A learner may tact a cow flawlessly yet be unable to answer 'What says moo?' with no cow in the room, because those are different skills under different controlling conditions. Intraverbal teaching deliberately builds those bridges from existing tacts and echoics.
Weak intraverbal repertoires often masquerade as social difficulty. Conversation is intraverbal chains - each turn occasioned by the last - so a learner who can label and request but not respond to language will stall in exactly the peer interactions families care most about. That is why intraverbal goals sit at the center of many school-age programs.
Good intraverbal data distinguishes rote from flexible responding. A learner who answers 'What do you eat?' only with 'apples' has a memorized pair, not a repertoire; varied, contextually sensible answers across askers and settings are the real measure, and programs track that variety deliberately.