Open Access Research article

“It’s just a theory”: trainee science teachers’ misunderstandings of key scientific terminology

James David Williams

Author Affiliations

School of Education and Social Work, University of Sussex, Falmer, Brighton, BN1 9QQ, UK

Evolution: Education and Outreach 2013, 6:12  doi:10.1186/1936-6434-6-12

Published: 27 June 2013



This article presents the findings from a survey of 189 pre-service science teachers who were asked to provide definitions of key scientific terms ('theory'; 'fact'; 'law'; 'hypothesis'). The survey was a scoping and mapping exercise to establish the range and variety of definitions.


Graduates on a pre-service science teacher training course were asked to complete a short, free response survey and define key science terminology a >95% response rate was achieved and respondents definitions were categorised according to a best fit model.


In some cases, definitions contrary to accepted scientific meanings were given. In other cases, terminology was defined in a wholly non-scientific way, e.g., one-fifth of the respondents defined a ‘law’ in the context of rules that govern society rather than in a scientific context. Science graduates’ definitions and their understanding of key terminology is poor despite their study of science in formal university settings (with many respondents being recent science graduates).


Key terminology in science, such as 'theory', 'law', 'fact', 'hypothesis', tends not to be taught and defined with consideration for the differences in meaning that different audiences/users give to them. This article calls for better instruction for pre-service science teachers’ in the importance of accurate and precise definitions of key science terminology in order to better differentiate between the scientific and colloquial usage of key terms.

Scientific language; Scientific definitions; Theory; Law; Fact; Hypothesis