Origin: Latin suffix -al
Interpersonal has 2 different meanings across 1 category:
occurring among or involving several people
"interpersonal situations in which speech occurs"
Between two or more people.
"The interpersonal skills she developed during college helped her communicate effectively between colleagues in the workplace."
In plain English: Interpersonal means relating to how you interact with other people.
"Good interpersonal skills are essential for building strong relationships with colleagues and friends."
The word interpersonal combines the prefix inter- with personal to describe relationships between people. It entered English as a straightforward formation from these two existing parts without a shift in meaning.