Key Facts
- Hangul: 무겁다 (mugeopda)
- Meaning: heavy
- Part of speech: adjective (형용사)
- Level: A2
- Stem: 무겁
- Class: ㅂ-irregular
- Spoken as: [무겁따]
What Does 무겁다 Mean?
무겁다 is used first for physical weight: 가방이 무겁다 (the bag is heavy). It also stretches to feelings and atmosphere, so 마음이 무겁다 means a heavy heart and 분위기가 무겁다 describes a tense mood. The thing described takes 이/가. Because it is a descriptive word, it already works as 'is heavy' without any extra verb, and -고 싶다 does not attach to it.
How Do You Pronounce 무겁다?
By itself the word is said [무겁따]: the ㅂ closes the syllable and makes the next consonant tense. Forms that keep the ㅂ work the same way: 무겁습니다 is [무겁씀니다] and 무겁지 않아요 [무겁찌 아나요]. Once the ㅂ has turned into 우, the word reads as written: 무거워요. In the past modifier 무거웠던 it is the past ㅆ that tenses the next sound: [무거웓떤].
How Do You Use 무겁다 in a Sentence?
이 가방은 너무 무거워요.
This bag is too heavy.
너무 (too) is placed before the adjective, and 이 가방은 is the topic. 무거워요 is the polite present with the ㅂ already turned into 우.
짐이 무거우면 제가 도와줄게요.
If your luggage is heavy, I will help.
A conditional: in 짐이 무거우면, the ㅂ of the stem and the 으 of the conditional ending combine into 우. The offer 도와줄게요 comes in the main clause.
무거운 상자를 같이 들었어요.
We lifted a heavy box together.
Here the adjective is placed before the noun as 무거운, so it modifies 상자를. 같이 들었어요 uses 들다, the verb for lifting.
How Does Mugeopda Conjugation Work?
무겁다
| Form | Korean | Romanization | Rule |
|---|---|---|---|
| Polite present | 무거워요 | ||
| Polite past | 무거웠어요 | ||
| Polite future (plan) | 무거울 거예요 | ||
| Polite future (intention or guess) | 무겁겠어요 | ||
| Formal present | 무겁습니다 | ||
| Formal past | 무거웠습니다 | ||
| Formal future | 무거울 것입니다 | ||
| Casual present | 무거워 | ||
| Casual past | 무거웠어 | ||
| Casual future | 무거울 거야 | ||
| Because / and then | 무거워서 | ||
| Conditional (if) | 무거우면 | ||
| Present modifier (before a noun) | 무거운 | ||
| Past modifier (before a noun) | 무거웠던 | ||
| Future modifier (before a noun) | 무거울 | ||
| Negative with 안 (short) | 안 무거워요 | ||
| Negative (long form) | 무겁지 않아요 |
| Form | Korean | Sound if different |
|---|---|---|
| Polite present | 무거워요 | — |
| Polite past | 무거웠어요 | [무거워써요] |
| Polite future (plan) | 무거울 거예요 | [무거울꺼예요] |
| Polite future (guess) | 무겁겠어요 | [무겁께써요] |
| Formal present | 무겁습니다 | [무겁씀니다] |
| Formal past | 무거웠습니다 | [무거웓씀니다] |
| Formal future | 무거울 것입니다 | [무거울꺼심니다] |
| Casual present | 무거워 | — |
| Casual past | 무거웠어 | [무거워써] |
| Casual future | 무거울 거야 | [무거울꺼야] |
| Because / and then | 무거워서 | — |
| Conditional (if) | 무거우면 | — |
| Modifier, present | 무거운 | — |
| Modifier, past | 무거웠던 | [무거웓떤] |
| Modifier, future | 무거울 | — |
| Short negative | 안 무거워요 | — |
| Long negative | 무겁지 않아요 | [무겁찌 아나요] |
Is 무겁다 Regular or Irregular?
무겁다 is ㅂ-irregular. When an ending starting with a vowel follows, the stem-final ㅂ turns into 우 and then merges with the ending: 무겁 + 어요 becomes 무거워요. Before a consonant the ㅂ stays, giving 무겁습니다. Not every word whose stem ends in ㅂ does this, so each one has to be learned; the lesson on ㅂ-irregular verbs and adjectives lists the common ones.
Common Mistake with 무겁다
Wrong: ✗ 무겁어요
Correct: ✓ 무거워요
Why: Learners attach 어요 straight to the stem. The ㅂ cannot stay in front of a vowel in this class, so it has to become 우, and 무거워요 is the result. The same change gives 무거우면 and 무거운.
무겁다 Versus 가볍다 and 두껍다
| Word | How it differs |
|---|---|
| 가볍다 | 가볍다 is the opposite: light in weight. |
| 두껍다 | 두껍다 means thick. A thick book can also be heavy, but the two words describe different things. |
Moving a Box of Books
Two housemates are packing for a move. One has filled a box with books and the other checks its weight.
Sora
이 상자는 무거워요?
I sangjaneun mugeowoyo?
Is this box heavy?
Jun
네. 책이 많아서 무거워요.
Ne. Chaegi manaseo mugeowoyo.
Yes. It’s heavy because there are lots of books.
Sora
어제 가방도 무거웠어요.
Eoje gabangdo mugeowosseoyo.
The bag was heavy yesterday, too.
Jun
무거우면 같이 들어요.
Mugeoumyeon gachi deureoyo.
If it’s heavy, let’s lift it together.
무거워요 describes the box now, 무거웠어요 describes yesterday's bag, and 무거우면 sets a condition for lifting together. No extra word meaning “is” appears before the adjective. The subject can be left out of the last line because the box is already clear.
Heavy Things, Heavy Feelings and a Heavy Mood
짐이 무겁다 means that luggage or a load is heavy. 짐 can cover the things you are carrying as a group, while 가방 identifies a bag. At a station or while moving house, the phrase tells someone about the effort of carrying the load without giving a numerical weight.
마음이 무겁다 literally describes the heart or mind as heavy. It means feeling burdened, worried or troubled. A person might feel this after bad news or before a difficult conversation. The phrase names an emotional state; it does not describe the physical weight of the heart.
분위기가 무겁다 means the atmosphere feels serious, tense or sombre. It can describe a room after an uncomfortable announcement. The subject is the shared mood, rather than one person's private feeling. Compare 마음 and 분위기 to tell whether the speaker is describing an individual or the whole scene.
입이 무겁다 literally means “the mouth is heavy”. As a set expression, it describes someone who is discreet and does not readily reveal things. A person trusted with a secret may be described this way. The phrase concerns how freely they speak, rather than the weight or size of their mouth.
Where Will You Hear 무겁다?
In travel talk, 무거워요 often comes up while lifting a suitcase, wearing a backpack or offering help with bags. It gives a personal assessment of weight. A small bag can still be heavy, so size and weight need separate descriptions.
In reviews, a book or film can feel heavy because its subject is serious. This figurative use is about the experience of reading or watching. A physically heavy book and a story with a heavy mood are different possibilities, and the surrounding sentence tells you which one is meant.
무겁다 is neutral vocabulary. 무거워 is casual, 무거워요 is polite, and 무겁습니다 fits a more formal statement. A label or written description may use the dictionary form 무겁다. The physical and figurative senses work across these styles; the ending changes the sentence's relationship to the listener.
Why Is It 무거운 상자?
무거운 is the form placed directly before a noun to describe it as heavy. 무거운 상자 is a noun phrase, “a heavy box”; 상자가 무거워요 is a sentence, “the box is heavy”. The adjective changes shape because it has a different job in the sentence.
무겁다 follows the adjective modifier pattern, so 무거운 describes a current property. An action verb's present modifier often ends in 는, but copying that pattern here would give the wrong result. The table's 무거웠던 points back to a remembered past state, rather than serving as the ordinary description of a box now.
The ㅂ change is a spelling change in conjugation. The tense sound in 무겁다 is a pronunciation change. Keep those two processes separate: 무거워요 loses the written ㅂ, while 무겁습니다 keeps it even though the following sound becomes tense.
| Related word | Meaning | Useful connection |
|---|---|---|
| 무게 | weight | Names the quantity that can be measured. |
| 짐 | luggage / load | Describes what someone is carrying. |
| 가볍다 | to be light | Gives the opposite end of the weight scale. |
| 들다 | to lift / hold | Names an action made harder by a heavy object. |
For carrying luggage through a terminal, the airport vocabulary lesson supplies the travel setting and words you may need alongside 무겁다.
Mini Drill: a Heavy Adjective
- Give the polite present of 무겁다.
- Complete “a heavy box”: ____ 상자.
- Give “if it is heavy” from the table.
- Does the formal 무겁습니다 retain the written ㅂ?
Show drill answers
- 무거워요.
- 무거운 상자.
- 무거우면.
- Yes. The consonant ending keeps it.
Quick Self-Test
- Does 분위기가 무겁다 describe physical weight?
- Which related noun means measurable weight?
- What quality does 입이 무겁다 describe?
Show answers
- No. It describes a serious, tense or sombre atmosphere.
- 무게.
- Discretion: someone does not readily reveal things.
Frequently Asked Questions
Why Is It 무거워요 and Not 무겁어요?
The class is ㅂ-irregular, so the ㅂ changes into 우 before a vowel ending, and 우 + 어 becomes 워.
Does 무겁다 Only Describe Weight?
No. It can also describe a mood or a heart, as in 마음이 무겁다 or 분위기가 무겁다.
Can I Attach the 'Want to' Ending to 무겁다?
No. -고 싶다 attaches to verbs, not to descriptive words such as 무겁다.
How Do I Say 'a Heavy Box'?
Use the modifier 무거운 before the noun, as in 무거운 상자.
Which Words Are Related to 무겁다?
What Should You Learn Next?
Learn 무겁다 together with 가볍다 so you have both ends of the scale, then see 들다 for the action of lifting. You can check other forms in the Korean verb conjugator or browse the Korean verb dictionary.