biochemical oxygen demand: meaning, definition, pronunciation and examples
C1/C2Technical / Scientific / Academic
Quick answer
What does “biochemical oxygen demand” mean?
A measure of the amount of dissolved oxygen consumed by microorganisms in water while they break down organic matter.
Audio
Pronunciation
Definition
Meaning and Definition
A measure of the amount of dissolved oxygen consumed by microorganisms in water while they break down organic matter.
A key indicator of water pollution, quantifying the organic load in a water sample by measuring the oxygen required for its aerobic decomposition over a specific period, typically five days (BOD5). It is used to assess the effect of wastewater on receiving waters.
Dialectal Variation
British vs American Usage
Differences
No significant lexical differences. Spelling follows regional norms (e.g., 'analysed' vs. 'analyzed' in surrounding text). The abbreviation BOD is universal.
Connotations
Purely technical and neutral in both varieties.
Frequency
Equally common in environmental science and engineering contexts in both regions.
Grammar
How to Use “biochemical oxygen demand” in a Sentence
The [effluent] has a high biochemical oxygen demand.Scientists measured the biochemical oxygen demand of the [river water].A [BOD test] determines the biochemical oxygen demand.Vocabulary
Collocations
Examples
Examples of “biochemical oxygen demand” in a Sentence
verb
British English
- The sample was left to incubate so we could BOD it.
- They are BODing the effluent weekly.
American English
- We need to BOD this wastewater sample.
- The lab BODed the influent and effluent.
adjective
British English
- The BOD reading was alarmingly high.
- We analysed the biochemical oxygen demand results.
American English
- The BOD test is a standard procedure.
- They reviewed the biochemical oxygen demand data.
Usage
Meaning in Context
Business
In environmental compliance reports: 'The factory's discharge must meet permissible limits for biochemical oxygen demand.'
Academic
In research papers: 'The biochemical oxygen demand was correlated with upstream agricultural activity.'
Everyday
Rarely used in everyday conversation. Might appear in news reports about pollution: 'The spill caused a spike in the river's BOD.'
Technical
Core term in environmental engineering and hydrology: 'The design of the wastewater treatment plant aims to reduce biochemical oxygen demand by 90%.'
Vocabulary
Synonyms of “biochemical oxygen demand”
Neutral
Weak
Vocabulary
Antonyms of “biochemical oxygen demand”
Watch out
Common Mistakes When Using “biochemical oxygen demand”
- Using 'biological oxygen demand' interchangeably is generally accepted but 'biochemical' is more precise. Misspelling as 'biochemical oxigen demand'. Incorrectly treating it as a verb, e.g., 'The waste biochemical oxygen demands the river.'
FAQ
Frequently Asked Questions
No. BOD measures oxygen consumed by microorganisms breaking down organic matter. COD (Chemical Oxygen Demand) measures oxygen equivalent of all oxidizable matter (organic and inorganic) using a strong chemical oxidant.
The 5-day period (BOD5) is a conventional, practical timeframe that represents a significant portion of the total degradation process without being excessively long for routine analysis.
BOD is expressed in milligrams of oxygen consumed per litre of sample (mg/L) over the incubation period, e.g., mg/L BOD5.
High BOD is caused by the discharge of organic waste, such as sewage, food processing waste, agricultural runoff, or paper mill effluent, which provides food for bacteria and other decomposers.
A measure of the amount of dissolved oxygen consumed by microorganisms in water while they break down organic matter.
Biochemical oxygen demand is usually technical / scientific / academic in register.
Biochemical oxygen demand: in British English it is pronounced /ˌbaɪ.əʊˌkem.ɪ.kəl ˈɒk.sɪ.dʒən dɪˈmɑːnd/, and in American English it is pronounced /ˌbaɪ.oʊˌkem.ɪ.kəl ˈɑːk.sɪ.dʒən dɪˈmænd/. Tap the audio buttons above to hear it.
Learning
Memory Aids
Mnemonic
Think 'BOD' as in 'Body of Decay' – it's the oxygen demand of decaying organic matter in water.
Conceptual Metaphor
WATER PURITY AS BREATHABILITY (High BOD 'suffocates' a river.)
Practice
Quiz
What does a high biochemical oxygen demand (BOD) indicate about a body of water?