alternate

alternate — verb

1. to keep switching from one thing or state to another, then back again, in a stea

1.verbintransitiveC1
Definition

to keep switching from one thing or state to another, then back again, in a steady, repeating pattern.

Example

Renata alternated between laughing and crying as she read her grandmother's letter.

alternate between A and B

The weather alternates between heavy rain and bright sunshine in early April.

subject is a natural phenomenon

Common collocations
  • alternate between
  • alternate with
  • moods alternate
  • rapidly alternate
Synonyms
  • fluctuate

    stresses change in level or amount, not paired items

  • oscillate

    more formal, often for opinions or emotions

  • swing

    informal, suggests larger or sudden shifts

Grammar Patterns

alternate between A and B

alternate with

Usage Note

Most often intransitive and followed by 'between' (with two items joined by 'and') or 'with' (one item paired with another). Distinguish from sense 2, which takes a direct object and means causing the switching.

Common Mistakes

The lights alternated red to green.
The lights alternated between red and green.
use 'between … and …', not 'from … to …', for the back-and-forth pattern.

2. to deliberately arrange two items in turns, so that each takes its place again a

2.verbtransitiveC1
Definition

to deliberately arrange two items in turns, so that each takes its place again and again in a regular, repeating sequence.

Example

The chef alternates layers of pasta with cheese sauce when she builds her lasagne.

alternate A with B for paired items

Coach Lin alternates short sprints and long jogs to keep his runners fresh.

alternate A and B for two activities

Common collocations
  • alternate layers
  • alternate crops
  • alternate scenes
Synonyms
  • rotate

    stresses cycling through three or more items

  • interleave

    more technical, used for layers or data

Grammar Patterns

alternate A with B

alternate A and B

Usage Note

Subject is usually a person or organisation that controls the pattern. Pairs naturally with 'with' for one item plus its partner, and with 'and' for two items treated equally.

Common Mistakes

She alternates her medicine every two days.
She alternates her medicine with vitamins every two days.
the transitive sense needs both items, not just one.

alternate — adjective

alternate — noun

Word family

Synonym discussion

Sense: adjective/3

When you need a second option to fall back on, all four words are close, but they pull in different directions. 'Alternate' (in this 'backup' sense) is mostly American — Americans happily say 'an alternate route' or 'an alternate plan', while British speakers usually feel 'alternative' is the right word there. 'Alternative' is the safest choice in formal British writing and often hints that the new option is genuinely different in style or thinking, not just a copy: 'an alternative lifestyle', 'alternative medicine'. 'Substitute' stresses one-for-one replacement of a specific item, especially in sport, cooking, or teaching: 'a substitute teacher', 'use honey as a substitute for sugar'. 'Backup', often before another noun, is the most informal and is common in technology and planning: 'a backup file', 'a backup generator'.

alternate ↗alternative ↗substitutebackup ↗

Common collocations

Nouns

Adverbs

Phrases

  • on alternate days
  • alternate between A and B
  • serve as an alternate

Prepositions

Etymology

LatinMiddle FrenchEnglish

Comes from the Latin verb 'alternare', meaning to do something by turns, which itself grew out of 'alternus' (one after the other) and 'alter' (the other of two). English picked up the adjective in the mid-1500s and the verb soon after, both keeping the core idea of two items taking turns. The 'backup' meaning of the adjective and the 'stand-in' noun are mostly American developments from the 1800s.