Holy means set apart for God or connected to the divine. Something holy isn't ordinary: it's sacred, special, and deserving of deep respect. A holy place, like a church, temple, or mosque, is where people worship and feel close to God. Holy writings, like the Bible or Qur'an, contain teachings that believers consider divinely inspired. Holy days, like Christmas, Easter, Ramadan, or Yom Kippur, mark important religious events.

When believers call God holy, they mean God is pure, perfect, and completely good. Religious leaders like priests, rabbis, or monks dedicate their lives to holy work: serving God, studying sacred texts, and helping others grow spiritually.

People also use holy more casually. If you say something is your “holy grail,” you mean it's the ultimate goal you're seeking. The phrase “holy cow!” expresses surprise or amazement, though it doesn't have religious meaning anymore.

Different religions have different ideas about what makes something holy, but the core idea remains: holiness separates the sacred from the everyday, marking what a community considers most important and worthy of reverence.