Lower middle class (shopkeepers and clerical staff etc.) WordNet 3.0 & Open English WordNet

Petite bourgeoisie is a French term that refers to a social class composed of semi-autonomous peasants and small-scale merchants whose politico-economic ideological stance in times of socioeconomic stability is determined by reflecting that of a haute bourgeoisie with which the petite bourgeoisie seeks to identify itself and whose bourgeois morality it strives to imitate. Wikipedia

Social class Wikidata

An aspirational socio-economic class comprising small-scale capitalists such as small-business owners, managers, and some skilled professionals. Wiktionary

A social class of that bourgeoisie that typically works alongside their employees if they have any, exemplified by shopkeepers and professionals. Wiktionary

Social class. Wiktionary (translation)