スーパーに行く。

The word 'スーパー' (sūpā) is a shortening of the English word 'supermarket'. It was adopted into Japanese likely in the mid-20th century as supermarkets became more common globally. The 'ー' indicates a lengthened vowel sound. 'に' (ni) is a particle indicating direction or destination, and '行く' (iku) means 'to go'. Therefore, the phrase literally means 'to go to the supermarket'. Supermarkets, as a concept, originated in the United States in the 1930s, offering a self-service shopping experience for groceries, which was a significant departure from traditional smaller shops where goods were often dispensed by clerks. This model was eventually adopted worldwide, including in Japan, where 'スーパー' became the common term.