Lexical items are the basic building blocks of a language, encompassing words, phrases, and expressions that carry meaning. They can include single words like dog or happiness, as well as multi-word expressions such as kick the bucket or in the long run. Each lexical item has its own meaning and usage, contributing to effective communication. In linguistics, lexical items are categorized into different types, such as nouns, verbs, adjectives, and adverbs. Understanding these categories helps in grasping how words function within sentences. Lexical items also play a crucial role in language acquisition, as learners build their vocabulary by recognizing and using these meaningful units.