Definition

1. Verb:
   • To become flat or flatter; to lose elevation, curvature, or unevenness.
   • To make something flat or flatter; to level or smooth out.

Usage

The verb "flatten out" describes the process of something becoming physically level or less steep. It can be used both intransitively (the thing itself flattens out) and transitively (someone flattens something out). It often describes changes in terrain, surfaces, or abstract concepts like graphs or trends.

Examples

• Intransitive use:
  • The road finally flattened out after the long, steep hill.
  • The graph shows sales rising sharply before flattening out in the third quarter.
• Transitive use:
  • She used a rolling pin to flatten out the dough.
  • The construction crew worked to flatten out the bumpy field.

Advanced Usage

• In Aviation: Describes an aircraft's action of transitioning from a climb or descent into level flight.
  • The pilot will flatten out the approach at 500 feet.
• In Economics/Statistics: Describes a trend or curve losing its slope and stabilizing.
  • Market growth is expected to flatten out next year.

Variants and Related Words

• Flatten (verb): The base form, meaning to make or become flat. "Flatten out" often emphasizes the process or result of achieving a level state.
• Flattened (adjective): Describes something that has been made flat.
• Flattener (noun): Something that causes flattening.

Synonyms

• Level out: To become level.
• Smooth out: To make a surface smooth.
• Even out: To become even or uniform.

Related Phrasal Verbs

• Flatten down: To press something so it lies flat against a surface.
  • He flattened down his hair after wearing a hat.
• Flatten against: To press oneself tightly against a surface.
  • The animal flattened itself against the wall to hide.

Related Idioms

• Flatten the curve: (Epidemiology/Public Health) To slow the rate of infection to prevent overwhelming healthcare systems.
  • Social distancing measures helped flatten the curve. (Note: This idiom uses the base verb "flatten," not the phrasal verb "flatten out.")

Verb

1. become flat or flatter
   • The landscape flattened