The simplification of the political landscape in terms of ‘left’ and ‘right’ is common across most democracies, if not most of the world. This would suggest that the terminology has a shared core meaning in different political contexts. While no such stable element has been established in the political science literature, various potential dividing lines that may form the core meaning have been proposed. This paper is the most extensive comparative study to our knowledge that evaluates these proposals by studying responses to open‐ended survey questions on what voters associate with the terms ‘left’ and ‘right’. Data from eight different democratic political contexts are analysed using quantitative text analysis methods. The results demonstrate varied support for the different explanations. Evidence is found in all contexts for the hypothesis that acceptance of inequality divides left‐ from right‐wing politics. That the left‐right dimension is a divide between those for and against government intervention in the economy, or between those for change and against change, is mostly congruent with our findings. We find less evidence that either secular/religious divisions, or different conceptions of equality, consistently differentiate left from right. Our findings point towards the existence of a context‐independent underlying dimension of left‐right competition.