half brother
B1neutral
Definition
Meaning
A male sibling with whom one shares only one biological parent.
A man who is one's brother through one shared parent, either biological or adoptive. Can also refer to a male considered as a brother through strong social or familial bonds, though this is less common.
Linguistics
Semantic Notes
The term is inherently relational and requires a context of shared parentage. It does not specify which parent (mother or father) is shared. The relationship can be biological or result from adoption/remarriage of a parent.
Dialectal Variation
British vs American Usage
Differences
No significant lexical difference. Both varieties use 'half brother'. Spelling: 'half-brother' (with hyphen) is also acceptable in both, though increasingly written as two words.
Connotations
Neutral in both, though the term inherently distinguishes the relationship from that of a 'full' or 'whole' brother.
Frequency
Equally common in both varieties.
Vocabulary
Collocations
Grammar
Valency Patterns
[Person A] is [Person B]'s half brother.[Person A] and [Person B] are half brothers.He has a half brother named X.She shares a half brother with him.Vocabulary
Synonyms
Neutral
Weak
Vocabulary
Antonyms
Usage
Context Usage
Business
Rare, except in contexts of family businesses, inheritance law, or biography.
Academic
Used in sociology, anthropology, genetics, and family law studies.
Everyday
Common in personal and family discussions.
Technical
Precise term in legal documents (wills, custody), genealogy, and genetics.
Examples
By CEFR Level
- This is my half brother, Tom.
- I have one half brother.
- My half brother lives in Manchester.
- We share the same mother, so he is my half brother.
- Although he's only my half brother, we grew up together and are very close.
- The inheritance laws treat half brothers differently from full siblings.
- His newfound half brother was the result of his father's first marriage, a fact revealed only recently.
- The genealogical study distinguished between paternal and maternal half brothers in the lineage analysis.
Learning
Memory Aids
Mnemonic
Think of a 'half' of a pie. A half brother shares only half (one) of the parental 'pie' with you.
Conceptual Metaphor
FAMILY IS A WHOLE; a half brother is a FRACTIONAL PART of that whole.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not directly translate as 'полубрат' – this is not standard. The Russian equivalent is 'единокровный брат' (sharing a father) or 'единоутробный брат' (sharing a mother), but 'сводный брат' means stepbrother. The English term 'half brother' covers both Russian concepts.
Common Mistakes
- Using 'stepbrother' incorrectly for half brother. A stepbrother has no biological parent in common; a half brother shares one.
- Omitting 'half' when the distinction is relevant to the context.
- Writing as one word: 'halfbrother'.
Practice
Quiz
What defines a half brother?
FAQ
Frequently Asked Questions
A half brother shares one biological parent with you. A stepbrother is the son of your step-parent from a previous relationship; you share no biological parents.
Yes, both 'half brother' (open form) and 'half-brother' (hyphenated) are widely accepted in modern English. The hyphenated form is slightly more traditional.
Yes, a half brother is a biological sibling (sharing 25% genetic overlap on average). The term 'half' is a genealogical descriptor, not a comment on the emotional reality of the relationship.
In casual settings, 'This is my brother, Sam' is common. If the distinction is necessary for clarity (e.g., explaining family structure), you can say 'This is my half brother, Sam. We share the same dad.'