Sentence:  Lisp is an applicative language. This means that it is structured around applying functions (operations) to a linked <WSD>list</WSD> of arguments that accompany those functions. ... A function call or function definition is only coded in the syntax of a <WSD>list</WSD>, which can be of an indefinite length. Thus, the <WSD>list</WSD> is the only data structure for a Lisp program. 
Meaning of the word marked with <WSD> tags:  A codified representation of a list used to store data or in processing; especially, in the LISP programming language, a data structure consisting of a sequence of zero or more items.