Without language, things between humans would get pretty confusing pretty fast. And even though the ways we communicate can be super-flexible, it's best to make sure we actually know what the words we're using really mean.
This becomes all the more important when we try to understand science, where words often take on highly specialised meanings. And that's why a team of researchers just published a master list of terms they would like everybody to stop getting wrong.
"In psychology, many terms are confused not only by new students but also by advanced students, psychology instructors, and science journalists," says one of the researchers, Scott Lilienfeld from Emory University.
This new work is actually a sequel to a paper Lilienfeld and colleagues published last year, in which they collected a list of the most "inaccurate, misleading, misused, ambiguous, and logically confused words and phrases in psychology, genetics, and science in general."
Now the team has compiled a new list of 50 pairs of words that mean completely different things, yet often get confused with each other.
We should all pay attention here, because such confusion affects not just the field of psychological science, but can impede and even harm public understanding of concepts we encounter every day.
For example, antisocial is a common term we use to describe shy, withdrawn people, but that's actually painting them with a much darker brush than they deserve, since antisocial behaviour usually involves being reckless and harming others.
Instead, an introvert who prefers to hang out at home rather than talk to other people is better described as asocial.
There's also psychopath versus sociopath - while psychopathy is a diagnosable personality disorder, sociopathy actually is not.
As the researchers point out, it's a colloquial term that can mean one of several concepts, and is so confusing they say we basically shouldn't use it at all.
The team also takes pains to explain how insanity and incompetence are not the same thing when it comes to legal charges - a person found legally insane in a trial cannot be found guilty of a crime, but if they're deemed incompetent, they can't even face a trial to begin with.
And when it comes to socially and culturally relevant terms, they also provide a clear breakdown of sex vs gender, race vs ethnicity, and the difference between prejudice and discrimination.
Those are just a few examples of the 50 word pairs Lilienfeld and colleagues have highlighted in their new paper.
They have helpfully broken the list up into six sections, covering not just specific disciplines within psychology, but also statistics and research methodology more broadly.
And the best part - the easy-to-read paper has been published online under open access, so you can go read the whole thing right now, for free.
To provide a starting point, below we've also included the entire list of word pairs for quick reference, so you can look up any terms that particularly catch your interest here.
Sensation, Perception, Learning and Memory
1. Negative reinforcement vs punishment
2. Renewal effect vs spontaneous recovery
3. Sensation vs perception
4. Working memory vs short-term memory
Social and Cultural Bases of Behaviour
5. Conformity vs obedience
6. Prejudice vs discrimination
7. Race vs ethnicity
8. Sex vs gender
9. Affect vs mood
10. Anxiety vs fear
11. Empathy vs sympathy
12. Envy vs jealousy
13. Repression vs suppression
14. Shame vs guilt
15. Subconscious vs unconscious
16. Antisocial vs asocial
17. Catalepsy vs cataplexy
18. Classification vs diagnosis
19. Delusion vs hallucination
20. Obsession vs compulsion
21. Psychopathy vs sociopathy
22. Psychosomatic vs somatoform
23. Schizophrenia vs multiple personality disorder
24. Serial killer vs mass murderer
25. Symptom vs sign
26. Tangentiality vs circumstantiality
27. Transgender vs transvestite
Research Methodology and Statistics
28. Cronbach's alpha vs homogeneity
29. Discriminant validity vs discriminative validity
30. External validity vs ecological validity
31. Face validity vs content validity
32. Factor analysis vs principle components analysis
33. Predictive validity vs concurrent validity
34. Mediator vs moderator
35. Prevalence vs incidence
36. Risk factor vs cause
37. Standard deviation vs standard error
38. Stepwise regression vs hierarchical regression
39. Clairvoyance vs precognition
40. Coma vs persistent vegetative state
41. Culture-fair test vs culture-free test
42. Delirium vs dementia
43. Disease vs illness
44. Flooding vs implosion
45. Hypnagogic vs hypnopompic
46. Insanity vs incompetence
47. Relapse vs recurrence
48. Stressor vs stress
49. Study vs experiment
50. Testing vs assessment
The paper was published in Frontiers in Education.