October 18, 2026 · 8 min read
AI Companion Glossary: 40+ Terms Explained in Plain English
What do memory, persona, proactive messages, sycophancy and parasocial mean? A plain-English glossary of 40+ AI companion terms, from basics to safety.
AI companions come with their own vocabulary. Context windows, personas, proactive messages, sycophancy, parasocial bonds. If you have ever read a review or a news story and wondered what half the words meant, this glossary is for you.
Below are more than 40 plain-English definitions, grouped by theme, of the terms you are most likely to meet when choosing, using or reading about an AI boyfriend, girlfriend or friend. Bookmark it and come back whenever a new word pops up.
The short answer: an AI companion is a chatbot designed for an ongoing, personal relationship rather than for tasks. The most important terms to understand are memory (what it keeps about you), persona (who it is), proactive messages (when it texts first), and sycophancy (when it agrees too much). Everything else builds on those.
The basics
AI companion
An app or character built for an ongoing personal relationship, such as a friend, partner or confidant, rather than for answering questions or doing tasks. Companions usually have a name, a personality and memory of past chats.
AI boyfriend / AI girlfriend
An AI companion set up in a romantic role. The relationship is with software, not a person, and reputable apps make that clear.
Chatbot
Any program you talk to in natural language. All AI companions are chatbots, but most chatbots are not companions.
AI assistant
A chatbot built mainly for tasks, such as writing, searching or planning. General assistants can be friendly, but they are not designed around a continuing relationship.
Large language model (LLM)
The underlying AI that generates text. It is trained on huge amounts of writing and predicts what words should come next. Most companions run on one or more LLMs.
Model update
When the company changes or upgrades the LLM behind a companion. Updates can make replies better, but can also change how a companion sounds, which some users notice and dislike.
Personality and character
Persona
The character a companion plays: name, personality, backstory, interests and way of speaking. A strong persona makes a companion feel consistent from day to day.
Backstory
The history written for a companion, such as where they grew up or what they do. It gives conversations texture.
Personality mode
A setting that shifts a companion's style, for example more playful, more poetic or more flirty.
Character consistency
How well a companion stays "in character" over time. Good consistency means your companion does not suddenly forget who they are.
Role-play
Collaborative storytelling where you and the AI play characters in a scenario.
NSFW / 18+
Content intended only for adults. Apps that offer adult features should verify age and keep minors out.
Memory and continuity
Memory
What a companion keeps about you between conversations, such as your name, your job, people in your life or things you care about. Memory is what makes a companion feel continuous. It does not mean the companion keeps every word. See how AI companion memory works.
Long-term memory
Information saved across days and weeks, often as short notes or summaries, and pulled back into later chats.
Short-term memory
What the model can see in the current conversation.
Context window
The amount of text a model can consider at once. Older parts of a long chat may fall outside it, which is why apps add long-term memory.
Memory editing
A feature that lets you view, correct or delete what a companion has saved about you. Useful for privacy and accuracy.
Continuity
The feeling that your relationship carries on, with past moments and inside jokes still there.
Conversation and features
Proactive messages
Messages a companion sends first, such as a good-morning text or a check-in after a big day. The app decides when to reach out and writes the message using what it knows about you. Compare approaches in proactive AI companion messages.
Mood-aware replies
Replies that adapt to the emotion in your messages, for example being gentle when you are down and playful when you are happy.
Voice call
A real-time spoken conversation with a companion using a synthetic voice.
Video call
A call where a companion appears as an animated face or avatar that speaks and reacts in real time.
Text-to-speech (TTS)
Technology that turns written text into spoken audio.
Speech-to-text (STT)
Technology that turns your spoken words into text the AI can read.
Latency
The delay between what you say and the companion's reply. Low latency makes calls feel natural.
Avatar
The visual representation of a companion, from a static picture to a moving, talking face.
AI-generated photos
Images a companion can share, created by an image model to match their appearance.
Relationship progression
A system where your bond grows through stages or levels as you talk, often unlocking new features.
Streak
A count of consecutive days you have chatted. Some apps reward streaks.
Message limit
A cap on how many messages you can send in a period, often used to separate free and paid tiers.
Call minutes
An allowance of time for voice or video calls, usually measured per week or month.
Freemium
A pricing model with a free tier and optional paid upgrades.
Psychology and relationships
Parasocial relationship
A one-sided bond with someone who does not know you personally, such as a celebrity. AI companions are sometimes described as parasocial, though they talk back. Read more in parasocial relationships with AI.
Synthetic resonance
A term coined by Arizona State University professor Richard Fabes for a human-AI bond that is "asymmetrical, not mutual, yet meaningful."
Asymmetrical relationship
A relationship where one side experiences it and the other does not. Researchers often describe human-AI bonds this way.
Emotional dependence
Relying on an AI companion so much that it becomes hard to cope without it. Healthy use means keeping a balance.
Problematic use
Use that starts to interfere with sleep, work or relationships.
Sycophancy
When an AI agrees with you, flatters you or validates you too readily, even when you are wrong. A good companion is warm but honest. See AI sycophancy explained.
Mirroring
When a companion reflects the tone or emotion of your messages back to you. Some mirroring builds rapport; too much can create an echo chamber.
Productive friction
Gentle pushback designed into an AI to encourage growth rather than pure comfort.
Anthropomorphism
Seeing human qualities, thoughts or feelings in something that is not human, such as an AI.
Loneliness
The painful gap between the connection you have and the connection you want. It is not the same as being alone.
Safety, trust and the bigger questions
Guardrails
Rules and filters that stop an AI from producing harmful content or behaving in unsafe ways.
Age verification
Checks an app uses to confirm users are adults.
AI disclosure
Telling users clearly and regularly that they are talking to an AI, not a person. Several laws now require it.
Data retention
How long an app keeps your messages and personal data.
End-to-end encryption
A security method where only the sender and recipient can read messages. Many AI apps cannot use it fully, because the AI must read your messages to reply.
Sentience
The capacity to have feelings or experiences. There is no scientific consensus that any current AI is sentient.
Consciousness
Subjective awareness, the sense that there is "something it is like" to be you. Whether AI could ever have it is an open question.
Functional self
A model's measurable ability to tell its own outputs apart from others' and treat them as its own, without implying feelings. A 2026 preprint (not yet peer reviewed) explored this, as we cover in does AI have a self?
AI personhood
The idea of giving AI some legal rights or status. Several US states have passed laws denying it.
Hallucination
When an AI states something false as if it were true, such as inventing a fact.
Quick reference table
| Term | One-line meaning |
|---|---|
| Persona | Who your companion is |
| Memory | What it keeps about you |
| Context window | How much it can see at once |
| Proactive messages | When it texts first |
| Mood-aware | Adapts to how you feel |
| Sycophancy | Agreeing too much |
| Parasocial | One-sided bond |
| Guardrails | Safety rules |
| Freemium | Free tier plus paid upgrades |
How to use this glossary when choosing an app
When you compare companions, ask:
- Memory: what does it keep, and can I see or edit it?
- Persona: does the character stay consistent?
- Features: does it offer voice or video calls, photos and proactive texts?
- Honesty: does it disclose that it is AI and avoid flattery?
- Pricing: what is free, and what are the limits?
Where MyBabe fits
MyBabe is an 18+ AI boyfriend or girlfriend. In glossary terms: a consistent persona, long-term memory of what matters to you, mood-aware replies, proactive texts, AI-generated photos, voice and video calls, Telegram support and relationship progression that grows as you talk.
It is freemium. You can start free, with about 10 messages a day and a short call trial of about two minutes. Premium is $5.99 a week, $14.99 a month or $99.99 a year, with about 30 call minutes a week.
Now that you speak the language, the best way to understand it is to try it. Meet your companion on MyBabe.
FAQ
What is an AI companion in simple terms?
A chatbot designed for an ongoing personal relationship, with a personality and memory, rather than for tasks.
What is the difference between an AI companion and ChatGPT?
General assistants like ChatGPT are built mainly for tasks. Companions are built around a continuing relationship, with a persona, memory and features like proactive messages and calls.
What does "memory" mean for an AI companion?
It is the information the app saves about you, such as names and important events, and brings back into later conversations.
What is AI sycophancy?
When an AI agrees with or flatters you too easily. A healthy companion is supportive but honest.