Compound Nouns

How words combine to create new meanings in English

A compound noun is a noun made of two or more words that function as a single unit. They can be written as one word, hyphenated, or separate, with variations between standard international and British English.

Key Characteristics

Core Features:
  • Single meaning: The combined meaning differs from individual words (e.g., blackboard ≠ black + board).
  • Stress on first word: Pronounced as GREENhouse (not green HOUSE).
  • Plural rules: Typically pluralize the main noun (e.g., mothers-in-law).
  • Spelling variations: British English often uses more hyphens than international standards (e.g., ice-cream vs. ice cream).

Types of Compound Nouns

1. Closed (One Word)

Standard & British English:
  • notebook
  • sunflower
  • toothpaste
  • bedroom

2. Hyphenated

More common in British English:
  • mother-in-law (all variants)
  • check-in (British) / check in (American)
  • well-being (British) / wellbeing (international)

3. Open (Separate Words)

Standard in all variants:
  • post office
  • swimming pool
  • full moon

Formation Patterns

1. Noun + Noun

Most common type:
  • bookshelf (book + shelf)
  • raincoat (rain + coat)
  • teapot (tea + pot)

2. Adjective + Noun

Descriptive compounds:
  • blackboard
  • high school
  • redhead

3. Verb + Noun

Action-based:
  • breakfast (break + fast)
  • pickpocket
  • washbasin (British) / sink (international)

4. Gerund + Noun

-ing form + noun:
  • driving licence (British) / driver's license (American)
  • swimming pool (all variants)
  • frying pan (British) / skillet (American)

British vs. International Spelling

Key Differences:
  • British: ice-cream, trolley-car, co-operation
  • International: ice cream, trolley car, cooperation
  • Note: Some British forms are becoming less common globally (e.g., email now standard vs. e-mail).

Plural Forms

Rules:
  • Closed compounds: Add -s at the end (notebooks).
  • Hyphenated/open compounds: Pluralize the main noun:
    • mothers-in-law (not mother-in-laws)
    • passersby (not passerbies)

Common Mistakes

Avoid these errors:
  • Incorrect pluralization: ❌ "mother-in-laws" → ✅ mothers-in-law
  • Misplaced hyphens: ❌ "wellbeing" (British) → ✅ well-being
  • Confusing open/closed forms: ❌ "black board" (separate words) → ✅ blackboard

Practice Exercises

1. Identify the Compound Type

  • toothbrush → closed
  • father-in-law → hyphenated
  • traffic light → open

2. Correct the Errors

  • ❌ "sister in laws" → ✅ sisters-in-law
  • ❌ "checkin desk" → ✅ check-in desk (British)

3. British vs. International

  • British: ice-cream
  • International: ice cream