What keyword means
Despite the name, a keyword is rarely a single word: "running shoes for tarmac" is a keyword just as much as "running shoes". In Spanish SEO both the English "keyword" and the translation "palabra clave" are in use, while German SEO has largely adopted the English word.
It helps to separate the keyword from the query. A query is what someone actually typed, with typos and word order of their own. A keyword is the term that groups many similar queries and that a page targets. Search Console, for example, shows queries; working with keywords means sorting them.
By length and volume, people distinguish generic keywords, short and searched a lot, from long tail keywords, longer and more specific, with fewer searches but a clearer intent. Behind each one sits a search intent: to learn, to compare, to buy or to reach a particular website.