One of the most practical study-skill questions ESL learners ask is deceptively simple: should I look words up in my own language, or entirely in English? Both a bilingual dictionary (translating between English and your native language) and a monolingual dictionary (English defined in English) have real value — the right choice depends heavily on your current level and your goal for that particular lookup. This guide compares both tools directly and gives concrete recommendations for each CEFR level.
1. What Each Dictionary Type Actually Does
A bilingual dictionary gives you a direct translation: look up "run," and you get the equivalent word or words in your own language. A monolingual dictionary — especially a learner's dictionary designed for ESL/EFL students — explains "run" using simplified English, usually with a restricted set of common defining words, plus example sentences showing the word in context.
Bilingual entry (English–Spanish): run (v) = correr
Monolingual learner's entry: run (v) — to move quickly using your legs, faster than walking. She runs five kilometres every morning before work.
2. The Case for Bilingual Dictionaries
- Speed: a direct translation is instantly clear, with no risk of misunderstanding a definition written in a language you are still learning.
- Good for absolute beginners who do not yet have enough vocabulary to read even a simplified English explanation.
- Useful for very technical or rare words where you need an exact equivalent quickly, such as legal or medical terminology.
The main risk of relying only on bilingual dictionaries is that a single English word frequently maps to several different words in another language depending on context, register, or collocation — and a quick bilingual lookup does not always capture which one applies.
3. The Case for Monolingual (Learner's) Dictionaries
- Builds English thinking: you stay inside the target language rather than constantly translating back and forth, which strengthens fluency over time.
- Shows nuance: good learner's dictionaries distinguish closely related meanings, register (formal/informal), and typical collocations.
- Comes with rich examples: seeing a word used in two or three natural sentences teaches grammar patterns alongside meaning.
- Reduces false friends risk: because you are reading a description of the concept, not a possibly misleading direct translation.
Beginners sometimes try to force themselves onto monolingual dictionaries too early, before they have the vocabulary to understand the definitions, which leads to frustration and looking up definition-words themselves in an endless chain.
4. Which Should You Use? A Level-by-Level Guide
| Level | Recommended primary tool | Notes |
|---|---|---|
| A1-A2 | Bilingual dictionary | Use it for quick, everyday lookups; don't worry about nuance yet. |
| B1 | Both, side by side | Try the monolingual learner's entry first; check the bilingual translation only if still unsure. |
| B2 | Monolingual learner's dictionary (primary) | Reserve bilingual dictionaries for rare, technical, or highly specific vocabulary. |
| C1-C2 | Monolingual dictionary (any, including native-level) | You should be comfortable with dictionaries written for native speakers by this stage. |
5. How to Read a Monolingual Definition Effectively
A common mistake at B1-B2 is reading only the first line of a definition and moving on. Good learner's dictionary entries contain several useful layers: the core definition, grammar information (countable/uncountable, transitive/intransitive), example sentences, and sometimes common collocations or a usage note.
- Read the full definition slowly, not just the first phrase.
- Read every example sentence — they teach grammar patterns and typical partner words.
- Check the part of speech and any grammar labels (e.g. [C], [U], [T], [I]).
- Write your own example sentence using the word, then compare it to the dictionary's examples.
- If several meanings are listed, identify which one fits the context where you first encountered the word.
6. A Hybrid Strategy That Works for Most Learners
Rather than choosing one dictionary forever, many successful learners use a simple hybrid routine: look up the word first in a monolingual learner's dictionary. If the definition and examples make sense, you have your answer and gained extra English exposure in the process. If it remains unclear after a genuine attempt, check a bilingual translation as a backup — then return to the English definition to confirm it matches.
Exercise — Match the Word to the Learner's Definition
Match each word to its simplified English definition.
- reluctant a) to say that something is true, especially when others disagree
- insist b) not willing to do something
- overwhelmed c) having too many things to deal with at once
To build the vocabulary skills that make dictionary lookups faster and more accurate, try LexFizz's Flash Cards and Match Up exercises, and see our related guide on how to improve English vocabulary.
Practise new vocabulary now
Use Flash Cards to review words you look up — free, no sign-up needed.
Try Flash Cards →Frequently Asked Questions
What is the difference between a monolingual and a bilingual dictionary?
A monolingual dictionary explains English words using English definitions (an English-to-English dictionary). A bilingual dictionary translates English words directly into your native language and vice versa.
Which type of dictionary is better for beginners?
Beginners (A1-A2) generally benefit more from a bilingual dictionary, because reading an all-English definition of an unfamiliar word can itself require vocabulary they do not yet have, which slows learning and causes frustration.
At what level should learners switch to a monolingual dictionary?
Most learners can start incorporating a learner's monolingual dictionary from around B1, once they have enough vocabulary to understand simplified English definitions, and should rely on it as their main tool by B2 and above.
Why do monolingual dictionaries help with fluency more than bilingual ones?
Monolingual dictionaries keep you thinking entirely in English, reinforcing word associations, example sentences, and collocations in the target language, rather than constantly translating back and forth, which slows real-time processing.
What is a learner's dictionary and how is it different from a standard dictionary?
A learner's dictionary (such as those published specifically for ESL/EFL students) uses a restricted defining vocabulary of around 2,000-3,000 common words to write definitions, making entries far easier for non-native speakers to understand than a standard native-speaker dictionary.
Can I use both types of dictionary at the same time?
Yes, and many successful learners do. A common strategy is to look up an unfamiliar word first in a monolingual learner's dictionary, and only check the bilingual translation if the English definition is still unclear.
Do bilingual dictionaries risk teaching wrong meanings?
Yes. A single word in English often has several translations depending on context, and a bilingual dictionary entry may not capture register, collocation, or the exact nuance, leading learners to pick an inappropriate synonym in the wrong context.
What features should a good monolingual learner's dictionary have?
Look for a restricted defining vocabulary, multiple example sentences per meaning, clear labelling of word forms and collocations, frequency information, and audio pronunciation for both British and American English.
Are online dictionaries better than printed dictionaries for English learners?
Online learner dictionaries are generally more practical today because they include audio pronunciation, example sentence search, and instant cross-referencing, while printed dictionaries remain useful for focused study without digital distractions.
How can I check if I understood a dictionary definition correctly?
Try writing your own example sentence using the new word based on the definition, then compare it to the example sentences already given in the entry. If your sentence uses the word in a similar way, you have understood the meaning correctly.