# basal

/ˈbeɪsəɫ/ (US) · /bˈeɪsəl/ (UK)

Source: https://englishreference.com/word/basal
Updated: 2026-08-08

## Senses

### 1. forming the base

adjective · CEFR C1 · Technical

relating to or forming the bottom part or the base of something.

For teachers: relating to, located at, or forming the base or foundation of a biological or physical structure.

- The researchers examined the basal layer of the skin to see how new cells grow.
- The architectural integrity of the structure depends on the basal support columns, which distribute the weight evenly across the bedrock.

Usage: Often used in anatomy and botany to describe the lowest part of an organ or plant.

### 2. minimum for life

adjective · CEFR C1 · Technical

the lowest level of energy or activity needed to keep a living thing alive.

For teachers: relating to the minimum level of energy or physiological activity required to maintain the life of an organism at rest.

- Your basal metabolic rate is the number of calories your body burns just to stay alive.
- The patient's basal insulin levels remained stable throughout the night, indicating that the long-acting dosage was correctly calibrated.

Usage: Frequently appears in the phrase 'basal metabolic rate' (BMR).

### 3. evolutionary origin

adjective · CEFR C2 · Technical · Academic

describing a group of living things that branched off very early in their history.

For teachers: denoting a lineage or taxon that diverged earlier than other groups in a phylogenetic tree.

- Sponges are considered a basal group in the animal kingdom.
- The discovery of this fossil suggests that the species occupies a more basal position in the hominid lineage than previously assumed.

### 4. a base part

noun · CEFR C2 · Technical

a part or structure that forms the base of something.

For teachers: any biological or physical structure that serves as a base or foundation.

- The basal of the leaf was wider than the tip.
- Microscopic analysis revealed that the basal was composed of a different cellular matrix than the rest of the specimen.

## Examples

- The basal cells divide rapidly to replace lost tissue.
- The basal ganglia help control movement and are located deep within the brain.
- In geological surveys, the basal layer of the sedimentary rock formation revealed evidence of ancient river systems that once flowed through the region.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.