Cool MateThereby vs Thus
When to use each in English, with meaning, register, and examples.
Thereby
FormalBeyond 10,000 (less common)C1adverb
Thus
FormalTop 2,000 (common)B2adverb
Most common: Thus
| Thereby | Thus | |
|---|---|---|
| Pronunciation | 🇬🇧 /["/ˌðeəˈbaɪ/"]/🇺🇸 /["/ˌðerˈbaɪ/"]/ | 🇬🇧 /["/ðʌs/"]/🇺🇸 /["/ðʌs/"]/ |
| Meaning | in that way; as a result | for this reason; therefore |
| Example | Regular exercise strengthens the heart, thereby reducing the risk of heart attack. | Many scholars have argued thus. |
| Register | Formal | Formal |
| How common | Beyond 10,000 (less common) | Top 2,000 (common) |
| CEFR level | C1 | B2 |
| Part of speech | adverb | adverb |
| Collocations | thereby improving, thereby increasing, thereby allowing | thus it follows, thus far, thus far into, thus we conclude |
| Antonyms | indirectly, without effect, in no way | therefore, consequently |
| Common mistakes | Using 'thereby' in informal speech when it's not appropriate., Confusing 'thereby' with 'therefor', which has a different meaning., Neglecting to pair 'thereby' with a gerund. | Using 'thus' in casual conversations where 'so' is more appropriate., Confusing 'thus' with 'that' in terms of meaning., Using 'thus' incorrectly as a conjunction instead of an adverb. |
| Usage notes | Use 'thereby' in formal writing to indicate the result of an action. It's less common in everyday conversation and may sound overly formal. | Used primarily in writing or formal speech. It can sound too stiff or old-fashioned in casual conversation. Avoid using it in everyday chat. |
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Frequently asked questions: Thereby vs Thus
What's the difference between Thereby and Thus?
Thereby: in that way; as a result Thus: for this reason; therefore
Which is more common: Thereby and Thus?
Thus is the most common in everyday English.
Which is more advanced: Thereby and Thus?
Thereby is the highest level, at C1, on the CEFR scale.
Are Thereby and Thus the same CEFR level?
Thereby: C1, Thus: B2 on the CEFR scale.
What part of speech are Thereby and Thus?
Thereby: adverb, Thus: adverb.
Can you show an example of each?
Thereby: Regular exercise strengthens the heart, thereby reducing the risk of heart attack. Thus: Many scholars have argued thus.
Can I use Thereby and Thus interchangeably?
Not always. Thereby and Thus are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.