# Words for Different Levels of “Big”: From Sizeable to Astronomical

> Source: https://mem-app.com/blogs/words-for-different-levels-of-big (Mem-App blog, 2026-10-16)

“Big” is one of the first words we learn, and it ends up describing everything: a big house, a big problem, a big price. It works, but it doesn't tell your listener *how* big. Native speakers pick different words depending on the size, and often on the feeling they want to show.

In this post I walk through six words on a ladder, from mildly big to beyond reasonable. For each one you'll get the meaning, examples, synonyms, opposites and a quick tip on when to use it.

## The ladder at a glance

| Level | Word | Roughly means |
|---|---|---|
| 1 | **sizeable** | noticeably big |
| 2 | **substantial** | big in a solid, important way |
| 3 | **huge** | very big |
| 4 | **enormous** | far bigger than normal |
| 5 | **colossal** | so big it's hard to imagine |
| 6 | **astronomical** | beyond what seems reasonable |

---

## 1. sizeable

**UK** /ˈsaɪ.zə.bəl/ · **US** /ˈsaɪ.zə.bəl/ · *adjective*

**Meaning:** Fairly big; noticeably large.

**Examples**
- A sizeable crowd gathered outside.
- She earns a sizeable income.

**Synonyms:** considerable, hefty, decent-sized
**Opposites:** small, modest

**Tip:** A good word when something is clearly big but not extreme. It sounds neutral and works well at work. You will also see it spelled *sizable* in US English.

---

## 2. substantial

**UK** /səbˈstæn.ʃəl/ · **US** /səbˈstæn.ʃəl/ · *adjective*

**Meaning:** Large in amount, size or importance.

**Examples**
- The company made a substantial profit.
- There is substantial evidence for this.

**Synonyms:** considerable, significant, solid
**Opposites:** slight, minor

**Tip:** More formal than *big*. It is common in business, news and academic writing, especially with words like *profit*, *evidence*, *change* and *amount*.

---

## 3. huge

**UK** /hjuːdʒ/ · **US** /hjuːdʒ/ · *adjective*

**Meaning:** Very big, much larger than usual.

**Examples**
- That's a huge difference.
- They live in a huge house by the sea.

**Synonyms:** massive, giant, vast
**Opposites:** tiny, small

**Tip:** You probably know this one already. The lesson is its level: it sits clearly above *big*, and it's friendly in everyday conversation.

---

## 4. enormous

**UK** /ɪˈnɔː.məs/ · **US** /ɪˈnɔːr.məs/ · *adjective*

**Meaning:** Far bigger than normal; extremely large.

**Examples**
- He ate an enormous breakfast.
- The film was an enormous success.

**Synonyms:** immense, gigantic, massive
**Opposites:** tiny, minute

**Tip:** Stronger than *huge*, and it works for both things and ideas (an *enormous* effort, an *enormous* relief).

---

## 5. colossal

**UK** /kəˈlɒs.əl/ · **US** /kəˈlɑː.səl/ · *adjective*

**Meaning:** So big that it is hard to imagine.

**Examples**
- It was a colossal waste of time.
- A colossal statue stands in the harbour.

**Synonyms:** gigantic, mammoth, monumental
**Opposites:** tiny, minuscule

**Tip:** Dramatic and emphatic. It's often used for mistakes, failures and waste (a *colossal* mistake), and for very large structures.

---

## 6. astronomical

**UK** /ˌæs.trəˈnɒm.ɪ.kəl/ · **US** /ˌæs.trəˈnɑː.mɪ.kəl/ · *adjective*

**Meaning:** Extremely high, far beyond what seems reasonable. Mostly used for prices and numbers.

**Examples**
- Rent in the city is astronomical.
- The odds of winning are astronomical.

**Synonyms:** sky-high, exorbitant, extortionate
**Opposites:** reasonable, affordable

**Tip:** Use it for costs, prices, odds and figures, not for physical size. It also carries a feeling of complaint or shock.

---

## Same sentence, six levels

Let's use one sentence and change only the word:

> **“The bill was ___.”**

- The bill was **sizeable**. (clearly more than usual)
- The bill was **substantial**. (a serious amount)
- The bill was **huge**. (very big)
- The bill was **enormous**. (far more than expected)
- The bill was **colossal**. (almost hard to believe)
- The bill was **astronomical**. (completely unreasonable)

Same bill, six different messages.

## How to remember them

Reading a list once isn't enough. Words stick when you see them again just before you'd forget them. That's called spaced repetition, and it's what Mem-App is built around.

1. **Look up** a word in Mem-App's built-in dictionary to see the definition, examples, synonyms, opposites and UK/US pronunciation.
2. **Add it** to your list with one tap.
3. **Review it** when it's due and rate how it went: Easy, Good, Hard or Forgot. The next review adapts to you.

## Try it yourself

Starter is free to start: up to 50 words, and no ads.

👉 [Try Mem-App free](https://mem-app.com/app/)

Which theme should I cover next? Tell me in the comments or message me.

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Add these 6 words to your Mem-App flashcards: https://mem-app.com/app?utm_source=site&utm_medium=markdown&utm_campaign=pack-levels-of-big#/definitions?words=sizeable,substantial,huge,enormous,colossal,astronomical