In modern civil circulation, a significant number of contracts are those of adhesion. As confirmed by judicial practice, the joining side may not understand the contract’s content or have a mistaken notion about it. The aim of the article is to research the reasons and consequences of lack of language clarity on the contract’s terms for the side that joins the contract, in order to determine the ways to eliminate them. The empirical method, the methods of description and interpretation, and the theory of formal and dialectic logic are used in the article. The reason for not understanding a contract’s terms might not be the objective complexity of the text, but the fact that the contractor does not read it. A conclusion is made that juridical means of protecting a contract’s side that has concluded a contract due to wrongous influence, are not always effective. The legal and linguistic design of a contract implies using any means of visualization that lets the contractors comprehend the meaning of a contract.