commensal
Upper-Intermediate (B2)
IPA: /kəˈmɛnsl/
KK: /kəˈmɛnsl/
adjective
Definition
Describing a type of relationship where one organism benefits while the other is not harmed or helped.
Example
The commensal bacteria in our gut help with digestion without affecting our health negatively.
Conversation
Did you know that some organisms can have a commensal relationship with others?
Really? I didn't know that; what does that mean exactly?
It means one species benefits while the other isn't affected at all.
That's interesting! Nature has so many unique interactions like that.
Synonyms & Antonyms
Synonyms
symbiotic
mutualistic
cohabiting
Antonyms
parasitic
harmful
detrimental
noun
Definition
A living thing that benefits from a relationship with another organism, where one gains an advantage and the other is not harmed.
Example
The clownfish is a commensal that lives among the tentacles of sea anemones, gaining protection without harming them.
Conversation
Did you know that some birds are considered commensal with larger animals?
Really? How does that work?
Well, they follow the bigger animals to catch insects that get disturbed.
Root Explanation
Commensal → It is formed from "com-" (meaning together) and "mensalis" (from "mensa", meaning table). The word describes someone who shares a table or meal with others, hence living together in a communal way.
Memory Tip
Think of people eating 'together' ('com-') at the 'table' ('mensalis') — that's why commensal refers to someone who shares a meal.
Visually Confused Words
mensal
compensable