Engineering English
Big O Notation
Software Engineering · Last updated: July 30, 2026 · How this entry was written
Definition: A mathematical notation describing the upper bound of an algorithm's growth rate in time or space relative to input size. It characterizes the worst-case scenario of algorithm efficiency.
Example in context
“When analyzing the sorting algorithm, we used Big O notation to express its worst-case time complexity as O(n log n).”
“Sıralama algoritmasını analiz ederken, en kötü durum zaman karmaşıklığını O(n log n) olarak ifade etmek için Büyük O notasyonu kullandık.”
Where engineers use it
Big O notation is used in code reviews, algorithm design discussions, and performance benchmarking. Engineers rely on it to compare algorithm efficiencies and to decide which implementation to use for large-scale data processing.
Synonyms: big O, asymptotic notation, Landau notation
Practice: can you use “Big O Notation” at work?
A junior developer proposes an algorithm with O(n^2) complexity for a real-time system. Use Big O notation to discuss why it may be unsuitable.
Show a model answer
“Can you explain the Big O notation of this function?”
“Big O Notation” in 21 languages
| English | Big O Notation |
|---|---|
| Turkish | Büyük O notasyonu |
| French | notation grand O |
| German | O-Notation |
| Spanish | notación O grande |
| Chinese | 大O符号 |
| Arabic | تدوين O الكبيرة |
| Portuguese | notação Big O |
| Russian | O-нотация |
| Japanese | ビッグオー記法 |
| Italian | notazione O grande |
| Vietnamese | kí hiệu O lớn |
| Hindi | बिग ओ नोटेशन |
| Thai | สัญกรณ์โอใหญ่ |
| Indonesian | notasi O besar |
| Korean | 빅오 표기법 |
| Bengali | বিগ ও নোটেশন |
| Dutch | grote O-notatie |
| Swedish | stora O-noteringen |
| Finnish | iso O -merkintä |
| Ukrainian | нотація великого O |
Frequently asked questions
What does Big O Notation mean in engineering?
A mathematical notation describing the upper bound of an algorithm's growth rate in time or space relative to input size. It characterizes the worst-case scenario of algorithm efficiency. In Software Engineering, the term carries a usage-frequency rating of 10/10 in the Engineering English library.
How do you pronounce Big O Notation?
Big O Notation is pronounced /bɪɡ oʊ noʊˈteɪʃən/ (IPA). The Engineering English app plays audio for the term and checks your pronunciation with speech recognition.
How is Big O Notation used in a sentence?
Example from an engineering context: “When analyzing the sorting algorithm, we used Big O notation to express its worst-case time complexity as O(n log n).”
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