The word “catholic” most basically means “universal” or “according to the whole,” and only secondarily became the name of a particular church (the Catholic Church).

What does the word “catholic” mean?

At its root, “catholic” comes from Greek: katholikos , built from kata (“according to” or “about”) and holos (“whole”).

So the core idea is “regarding the whole,” which is why it is commonly translated as “universal” or “general.”

Over time, Christians used “catholic” to describe the universal church, as opposed to local groups or splinter movements.

That is how the phrase “Catholic Church” arose, meaning the church that was for all places and peoples, not just a regional sect.

Two main ways people use “catholic”

  1. Religious / Church sense
    • “Catholic” can mean “of the universal Christian church” in the early, broad sense.
 * More commonly today, it refers to the specific institution known as the Catholic Church (in practice, usually the Roman Catholic Church).
  1. Everyday English sense
    • In general English, “catholic” (lowercase) means “broad, wide-ranging, all-embracing.”
 * Example: “She has catholic tastes in music” = she enjoys a wide variety of music.

A bit of backstory (quick)

Early Christian writers were already using the term by around the early 2nd century to distinguish the “whole” church from breakaway groups.

From the late 2nd century onward, “catholic” could also mean “orthodox,” in the sense of holding the full, balanced Christian faith rather than a narrow or local teaching.

The Catholic Church’s own catechism still defines “catholic” as “universal,” in the sense of “according to the totality” or “in keeping with the whole.”

So whether in theology or in everyday talk, the word always keeps that basic idea of wholeness and universality.

TL;DR:
“Catholic” comes from Greek for “according to the whole” and means “universal.”

It names the universal Christian church historically and, in modern usage, usually refers to the Catholic Church, while in regular English it can mean “broad, all-embracing.”