speculate

speculate — verb

1. To think of possible explanations for something without having the information n

1.verbtransitive / intransitiveB2
Definition

To think of possible explanations for something without having the information needed to be certain.

Example

Without seeing the exam results, the students could only speculate about who passed.

speculate + about + noun phrase

Journalists speculated that the mayor would resign after the scandal broke.

speculate + that-clause

Common collocations
  • speculate about the cause
  • speculate on the outcome
  • speculate freely
  • speculate wildly
  • widely speculated that
Synonyms
  • guess

    Less formal and more spontaneous; does not imply a process of reasoning

  • conjecture

    More formal; suggests forming a theory from incomplete evidence

  • theorize

    Suggests a broader system of explanation, often with more structured reasoning

Antonyms
  • know

    Having certainty based on evidence rather than guesswork

Grammar Patterns

speculate + about/on + noun phrase

speculate + that-clause

Usage Note

Common with prepositions about and on to introduce the topic of speculation. The that-clause pattern is used when stating the specific guess or theory.

Common Mistakes

The police speculated a robbery.
The police speculated that a robbery had taken place.
When guess is stated as a full idea, use a that-clause, not a direct object.
I speculate you are right.
I think you are right.
For a firmly held belief, use think or believe, not speculate, which implies uncertainty.

2. To buy property, shares, or goods intending to resell them for more than they co

2.verbintransitiveB2
Definition

To buy property, shares, or goods intending to resell them for more than they cost — accepting the risk that prices may drop and money will be lost.

Example

Liang made a fortune by speculating in technology stocks before the market boom.

speculate in [type of investment]

Some investors prefer to speculate on currency movements rather than hold shares long-term.

speculate on [market]

Common collocations
  • speculate in stocks
  • speculate on property
  • speculate in currency
  • speculate heavily
Synonyms
  • trade

    Broader term; does not necessarily imply high risk or short-term profit motive

  • gamble

    More negative; suggests reckless risk-taking without analysis

Antonyms
  • invest

    Implies a longer-term strategy with careful research rather than betting on price movements

Grammar Patterns

speculate + in/on + financial asset

Usage Note

Subject is usually a person or institution acting in a financial context. Object is typically a financial asset (stocks, land, currency, commodities). Frequently used with prepositions in (the asset class) or on (the specific item or market).

Common Mistakes

She speculated a house.
She speculated in property.
Use a preposition (in/on) before the type of investment, not a direct object.

Word family

  • speculation
    nounB2
  • speculator
    nounB2
  • speculative
    adjectiveB2
  • speculatively
    adverbC1

Synonym discussion

Sense: verb/1

Guess is the most general and everyday word for forming an opinion without enough facts — it can be a quick, spontaneous answer. Conjecture is more formal and suggests building a theory from incomplete clues, often used in academic or analytical contexts. Theorize involves constructing a broader framework of ideas to explain something, usually with more systematic reasoning than speculation implies. Hypothesize is a scientific term meaning to propose a testable explanation that has not yet been proven. For example, you might guess the answer to a trivia question, conjecture about the writer's intention from a few passages, theorize about how ancient civilisations collapsed, or hypothesize that a certain protein causes the disease. Speculate, in this sense, sits between guess and conjecture — it suggests thinking through possibilities rather than a single guess, but without the formal structure of a theory or hypothesis.

guess ↗conjecturetheorizehypothesize

Common collocations

Nouns

Adverbs

Phrases

  • speculate that...
  • it is speculated that...

Prepositions

Etymology

LatinEnglish

From Latin 'speculatus', past participle of 'speculari' (to watch, to observe), from 'specula' (a lookout), from 'specere' (to look). The meaning evolved from 'observing and watching for signs' → 'forming theories based on observation' (16th century) → 'engaging in risky financial transactions' (18th century).