Esperanto opposites: how mal- doubles your vocabulary

Esperanto makes an opposite by putting the prefix mal- in front of a word: bona "good" → malbona "bad", granda "big" → malgranda "small", fermi "to close" → malfermi "to open". Learn one root and you know both ends of the scale. The tables below give 74 pairs by theme. Pronunciation guides split words into syllables, with the stressed syllable in capitals.

#How mal- works

Mal- is one of the ten official prefixes. The Fundamento (1905) explains it in one line: it denotes opposites, as in bona – malbona. PMEG defines it as "the directly opposite idea" and adds that it is used only where a direct opposite exists. It never changes the word class (see word building):

• Adjectives are the most common: varma "warm" → malvarma "cold".
• Verbs reverse the action: permesi "to allow" → malpermesi "to forbid".
• Adverbs and small words: frue "early" → malfrue "late", antaŭ → malantaŭ "behind".
• Nouns: lumo "light" → mallumo "darkness".

On its own mal- is also a root: malo "the opposite". La malo de "alta" estas "malalta". – "The opposite of 'high' is 'low'."

Stress follows the usual rule, the second-to-last vowel, so it normally stays off mal-: mal-BO-na, mal-FER-mi. In malpli "less", malplej "least" and maltro "too little" there are only two vowels, so the stress lands on the prefix: MAL-pli, MAL-plej, MAL-tro (PMEG).

malbona: mal-BO-namalbona/malˈbo.na/

malfermi: mal-FER-mimalfermi/malˈfer.mi/

malpli: MAL-plimalpli/ˈmal.pli/

#Size and quantity

#Temperature, light and touch

The colours page shows how hel- and malhel- make light and dark shades.

#Age, time and speed

#Quality, character and feelings

#Movement and actions

With verbs, mal- gives the reverse action.

With some verbs PMEG notes a sharper sense. Maldormi means to stay awake when you would normally sleep, and malhavi "to lack" means not having something you feel you should have.

#Place and direction

#Mal- versus ne

Ne only denies, while mal- states the opposite. Ne laŭdi "not to praise" says nothing bad, but mallaŭdi "to blame, to condemn" does. PMEG gives these contrasts:

So ne bona "not good" leaves the middle open, while malbona "bad" is the other end of the scale. The two can be combined, as in ne malbona "not bad".

#Opposites without mal-

Many opposites are two unrelated roots, so no mal- is needed. PMEG lists tago – nokto "day – night", komenci – fini "to begin – to end" and nigra – blanka "black – white" among its examples.

Three other cases need a note:

• Male and female use the suffix -in-, not mal-: viro "man" – virino "woman", patro "father" – patrino "mother". See suffixes.
• Always and never come from the correlatives: ĉiam "always" – neniam "never". See correlatives.
• Short alternatives exist beside a few mal- words: kurta beside mallonga, frida beside malvarma, liva beside maldekstra. PMEG says kurta and frida appear mostly in poetry and technical words (fridujo "refrigerator"), and that the mal- word always remains correct.

#How many words mal- gives you

On 8 October 2026 we counted the mal- words in the ReVo data behind our dictionary, which has 32,762 entries. An entry counted when its headword starts with mal- and ReVo files it as a derivation of another word with mal-. We left out the root mal- itself (malo, male) and look-alikes such as malto "malt" and malgraŭ "despite".

The result is 784 words, 2.4% of all entries, built on 463 different ReVo root articles. Without the prefix each would be one more word to memorise. In our list of the 1,000 most common words, 42 begin with mal-, led by malbona (rank 229), malgranda (268), malpli (297) and malnova (306).

#In sentences

Learn the most common words first, then add their opposites.

#Common questions

#How do you say the opposite of a word in Esperanto?

Put mal- in front of it: granda "big" → malgranda "small". The ending stays, so adjectives, verbs, adverbs and nouns all work.

#What is the difference between mal- and ne?

Ne means "not", mal- means "the opposite". Neutila is "of no use", while malutila is "harmful".

#Can you put mal- in front of any word?

No, only where a direct opposite exists. Many opposites are separate roots, such as tago – nokto "day – night".

#How many Esperanto words use mal-?

In the ReVo data we checked, 784 words are built with it (counted on 8 October 2026).

#Is the opposite of "man" malviro?

No. The female is marked with -in-: viro "man" → virino "woman".

#Sources

• PMEG – MAL
• PMEG – Prefixes
• Fundamento de Esperanto – Ekzercaro (affix explanations)
• ReVo (Reta Vortaro): mal- and every word in the tables, e.g. bona, malbona
• Frequency ranks: our list of the 1,000 most common words, counted in Tatoeba sentences (CC BY 2.0 FR)