Greek word · G2840

κοινόω

koinoō

to profane

In ordinary Greek, from κοινός ('common, shared'), it means 'to make common, to share, to communicate'. Greek-speaking Jews gave it a special religious sense: 'to make common' as opposed to holy, that is, to make ritually impure, to profane.

Appears 14 times in 11 verses of the Greek New Testament. · Updated November 01, 2026

What it means

κοινόω, -ῶ

[in LXX: 4Ma.7:6 א R* ;]

1. in cl., to make common.

2. In LXX, l.with, and NT (as κοινός, 2), to make ceremonially unclean, to profane (= cl., βεληλόω): Matthew 15:11, 18 15:20, Mark 7:15, 18 7:20, 23, Acts 21:28; pass., Hebrews 9:13.

3. to count unclean (cf. δικαιόω): Acts 10:15 11:9.†

SYN.: βεβηλόω. Thayer (see word κ.) mentions that Winer Notes the accuracy whereby the Jews are said to use κ. in addressing Jews, Acts 21:28, and β. when speaking to Felix, 24:6 (Cremer, 362) (AS)

From G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922), via STEPBible.org (CC BY 4.0).

In depth

From the study of Matthew 15:11

Range of meaning: In ordinary Greek, from κοινός ('common, shared'), it means 'to make common, to share, to communicate'. Greek-speaking Jews gave it a special religious sense: 'to make common' as opposed to holy, that is, to make ritually impure, to profane. Something 'common' (κοινός) was unfit to come near the sacred: food that was not kosher or had become contaminated, people in a state of impurity, a holy place that had been profaned.
Against the English: English 'defile' sounds like moral filth, sexual violation, or simply getting dirty. The Greek word belongs to the system of ritual status, holy versus common and clean versus unclean. That system decided who could eat sacred food, enter the temple courts, or share a table with the observant. 'Defile' is a fair translation, but it hides that this was technical purity vocabulary.
How it drifted: Most English readers today have no working purity system. So 'defile' has narrowed to a moral or hygienic meaning, and the shock of Jesus' saying is lost. He took the vocabulary of ritual status and applied it to moral wrongdoing from the heart.
Used elsewhere in the period: 1 Maccabees 1:47, 62 calls forbidden food κοινά, 'common things'. Under Antiochus IV, faithful Jews 'chose to die rather than be defiled by food'. 4 Maccabees 7:6 praises the martyr Eleazar for not making 'common' (ἐκοίνωσας) his stomach by eating defiled food. In the New Testament the word appears in Mark 7:15–23, in Acts 10:15 and 11:9 ('what God has cleansed, do not call common'), in Acts 21:28, where Paul is accused of having 'made common' the temple by bringing Greeks into it, and in Hebrews 9:13. In Mark 7:2 'common hands' is explained as 'unwashed'.

From the study of Hebrews 9:13

Range of meaning: Classical Greek: to make common or shared, to communicate. In Jewish Greek of the Second Temple period: to make "common", i.e. profane or ritually impure, the opposite of holy. Perfect passive participle: "having been defiled", in a lasting state of impurity.
Against the English: KJV "the unclean"; WEB/YLT/NASB "defiled"; BSB/NIV "ceremonially unclean". "Defiled" and "unclean" can sound like moral filth or physical dirt. The Greek pictures something moved out of the holy category into the "common" one.
How it drifted: English "unclean" and "defiled" slide easily into "sinful" or "dirty". In the Torah, impurity is a ritual status, often contracted unavoidably and without guilt.
Used elsewhere in the period: 1 Macc 1:47, 62: "common" (κοινά) foods that faithful Jews refused. Mark 7:2, 5, 15–23 ("defiled" hands, what "defiles" a person). Acts 10:14–15; 11:8–9 ("what God has cleansed, do not call common"). Acts 21:28 (Paul accused of having "defiled" the temple). The Greek Old Testament itself mostly uses μιαίνω and ἀκάθαρτος for Hebrew ṭāmēʾ, including in Numbers 19. Hebrews uses the idiom current among Jews of its own day.

From the study of Acts 10:15

Range of meaning: Koinos in ordinary Greek means "shared, held in common, public" (as in Acts 2:44, "they had all things in common"). Jewish Greek of the Second Temple period (roughly 500 BC to AD 70) also used it in a special sense: profane, ritually defiled, the opposite of holy, so something a Jew may not eat or touch. The verb koinoō means (1) to make common, to defile (Mark 7:15–23; Acts 21:28, where Paul is accused of having "defiled this holy place"), and (2) to declare or consider something common. BDAG puts Acts 10:15 and 11:9 under sense 2.
Against the English: KJV, ESV and YLT keep "common." BSB and NIV have "impure," WEB and NLT "unclean," and NASB (1995) "unholy." "Common" keeps the link with Peter's word in verse 14, but in modern English it sounds like "ordinary." "Unclean" and "impure" give the right meaning but blur it with akathartos ("unclean"), the separate word Peter also used in verse 14.
How it drifted: When the KJV was made, "common" as the opposite of "holy" or "set apart" was still understood. Today it mostly means "ordinary" or "widespread," so "call not thou common" can sound like "don't look down on it as plain."
Used elsewhere in the period: 1 Maccabees 1:47 and 1:62 (2nd century BC) describe pressure under Antiochus IV to sacrifice pigs and "common" animals, and faithful Jews who chose to die rather than eat koina. Mark 7:2 has to explain to Gentile readers that "common hands" means unwashed hands, which shows the sense was Jewish and needed explaining. The verb appears in Mark 7 for what "defiles" a person, and the meaning continues in Hebrews 9:13 and Revelation 21:27.

Where it appears

Matthew · 5

Matthew 15:11 κοινοῖ κοινοῖ defiles

A man is not defiled by what enters his mouth, but by what comes out of it.”

Here: 'Makes common'. This is the language of purity: it means making a person ritually unfit to come near what is holy. It was the exact charge in the hand-washing dispute, and here Jesus turns it around.
Matthew 15:18 κοινοῖ defile

But the things that come out of the mouth come from the heart, and these things defile a man.

Here: To make "common", meaning ritually unclean and unfit for what is holy. This is the exact word of the Pharisees' complaint about unwashed hands (vv.2, 11, 20). Jesus keeps their purity vocabulary but moves the source of impurity from outside the body to inside.
Matthew 15:20 κοινοῦντα κοινοῖ defiling, it defiles

These are what defile a man, but eating with unwashed hands does not defile him.”

Here: Literally "making common," meaning making someone ritually impure and unfit to come near what is holy. Jesus uses the Pharisees' own purity word but applies it to wrongdoing that comes from the heart.

Mark · 5

Mark 7:15 κοινῶσαι κοινοῦντα to defile, are defiling

Nothing that enters a man from the outside can defile him; but the things that come out of a man, these are what defile him.”

Here: Literally "to make common": in Jewish usage, to make someone ritually impure and so unfit for contact with the holy. It picks up the "common" (koinais) hands of 7:2.
Mark 7:18 κοινῶσαι; to defile?

“Are you still so dull?” He asked. “Do you not understand? Nothing that enters a man from the outside can defile him,

Here: In Jewish Greek, to make someone or something 'common', meaning ritually impure and unfit for contact with what is holy. This is the very word behind the dispute about 'common' (unwashed) hands in v2 and v5.
Mark 7:20 κοινοῖ defiles

He continued: “What comes out of a man, that is what defiles him.

Here: In the purity language of Jews of the period, 'to make common' meant to make someone unclean, unfit to come near what is holy. It is the very word of the dispute in 7:2 ('common', that is, unwashed, hands). Jesus keeps the word but says where real defilement comes from.
Mark 7:23 κοινοῖ it defiles

All these evils come from within, and these are what defile a man.”

Acts · 3

Acts 10:15 κοίνου. do call common.

The voice spoke to him a second time: “Do not call anything impure that God has made clean.”

Here: A command: "do not call or treat as common." It picks up Peter's word koinon ("common") from verse 14. Here it means to pronounce something profane, defiled and unfit for a holy people, not to make it so. The voice answers the exact word Peter used.
Acts 11:9 κοίνου. do call unholy.

But the voice spoke from heaven a second time, ‘Do not call anything impure that God has made clean.’
Acts 21:28 κεκοίνωκεν has defiled

crying out, “Men of Israel, help us! This is the man who teaches everyone everywhere against our people and against our law and against this place. Furthermore, he has brought Greeks into the temple and defiled this holy place.”

Here: A perfect tense: a past act whose result still stands. The holy place is now in a profaned state, cut off from its holy status until it is purified.

Hebrews · 1

Hebrews 9:13 κεκοινωμένους defiled

For if the blood of goats and bulls and the ashes of a heifer sprinkled on those who are ceremonially unclean sanctify them so that their bodies are clean,

Here: A perfect passive participle: "those who have been made common" and are now in that state. In Jewish usage "common" is the opposite of holy, meaning ritually unfit to approach the sanctuary. In Numbers 19 this comes from touching a corpse, which is not a moral failing.

Word data: STEPBible.org (CC BY 4.0), main text only.