The Negative Prefix on-
Put on- in front of an adjective to make its opposite, like English un- or im-: méiglech → onméiglech (impossible), bekannt → onbekannt (unknown).
How It Works
1. Making opposites
On- turns an adjective into its opposite:
- méiglech → onméiglech (impossible)
- praktesch → onpraktesch (impractical)
- bekannt → onbekannt (unknown)
- gedëlleg → ongedëlleg (impatient)
- gesond → ongesond (unhealthy), frëndlech → onfrëndlech (unfriendly)
2. The n always stays
The official spelling rules make on- an exception to the n-rule: the n is spoken and written before every consonant. The prefix in- in words from Latin or French works the same way: inkompetent.
Compare the verb prefixes an- and un-, which do follow the n-rule: akafen, ukucken (see u- and a- prefixes). So on- always keeps its n, but un- and an- lose it before most consonants.
3. Endings
The adjective takes its normal endings: en onpraktesche Mënsch, eng ongesond Loft, en onfrëndlecht Wiesen.
4. Nouns with on-
A few nouns also start with on-: d'Ongléck (accident, misfortune), d'Onrou (unrest), and nouns made with -keet such as d'Onméiglechkeet (impossibility).
5. On- or net?
You can often say the same with net: Dat ass net méiglech and Dat ass onméiglech are both correct, but onméiglech is stronger.
Examples (6)
- Et ass onméiglech, déi Streck an esou kuerzer Zäit ze lafen.
It is impossible to run that distance in such a short time.
The n of on- stays before m.
- Déi nei Verpackung ass schéin, awer onpraktesch.
The new packaging is nice, but impractical.
The n stays before p.
- Sief dach net esou ongedëlleg!
Don't be so impatient!
- De Schrëftsteller ass hei nach onbekannt.
The writer is still unknown here.
- Ech fannen déi Still ganz onbequeem.
I find those chairs very uncomfortable.
- Op der Autobunn ass en Ongléck passéiert.
There was an accident on the motorway.
Ongléck is a neuter noun with on-.
Common Mistakes
Dropping the n of on- by the n-rule.
Dat ass oméiglech.Dat ass onméiglech.On- is an exception: its n is always written, whatever consonant follows.
Dropping the n before g.
Sief net esou ogedëlleg!Sief net esou ongedëlleg!Even before g, b or p the prefix stays on-.
Dropping the n of in-.
Hien ass total ikompetent.Hien ass total inkompetent.The prefix in- follows the same rule as on-: the n always stays.
How It Connects
Learn This First
Before The Negative Prefix On-, learn Adjectives in -eg and -lech.
Related Patterns
- The N-Rule (Eifeler Regel)
On- is one of the official exceptions to the n-rule.
Level 1 - Separable Prefixes un- / u- and an- / a-Separable Prefixes Un- and an-
The verb prefixes u- and a- do follow the n-rule, unlike on-.
Level 2 - Nouns in -heet and -keet
An on- adjective can become a noun: Onméiglechkeet.
Level 4 - Nouns and Adjectives That Keep Their N
Like most adjectives and nouns, on- keeps its n before any consonant.
Level 4
Words in This Pattern
Practice The Negative Prefix on- in Bubblegum
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