A2adverb1K

Certainly

UK /["/ˈsɜːtnli/"]/US /["/ˈsɜːrtnli/"]/

Definition

without doubt

In simple words: Definitely; for sure.

Examples

  • Without treatment, she will **almost certainly** die.
  • Certainly, the early years are crucial to a child's development.
  • I'm certainly never going there again.
  • I certainly hope we can do this again.
  • She was certainly attractive but you couldn’t call her beautiful.
  • It is **certainly true** that individual earthquakes are difficult to predict with any accuracy.
  • This will certainly make them think again.
  • ‘May I see your passport, Mr Scott?’ ‘Certainly.’
  • ‘Do you think all this money will change your life?’ ‘Certainly not.’

Usage notes

Use 'certainly' when you want to emphasize affirmation or agreement. It is more formal than 'sure' and works well in professional settings, but might feel too strong in casual conversations.

Grammar pattern

standalone adverb

Memory hint

Think of 'certainly' as 'certainly yes'— like a strong, confident nod.

Collocations

  • certainly agree
  • certainly possible
  • certainly not
  • certainly true
  • certainly yes

Synonyms

  • definitely

Antonyms

  • uncertainly
  • doubtfully

Common mistakes

  • 'Certainly' is often incorrectly used in place of 'certain' in adjectives.
  • Learners might confuse 'certainly' with 'definitely' without noticing the subtle nuance.
  • Some learners use 'certainly' in inappropriate contexts, such as casual greetings.