Read the following passage carefully and answer the question given below it. Certain word/words are given in bold to help you to locate them while answering some of the questions.
Language formed during the prehistoric age among the human race as a means for communication and as a basis for thinking. We know little about the various steps in its formation;  but language now contains a great number of concepts which are a suitable tool for more or less ambiguous communication about events in daily life. These concepts are acquired gradually without critical analysis by using the language, and after having used a word sufficiently often we think that we more or less know what it is of course a well known fact that the words are not so clearly defined as they seem to be at first sight and that they have only a limited range of applicability. For instance, we can speak about a piece of wood, but we cannot speak about a piece of water. The word ' piece ' does not apply to liquid substances. Or, to mention another example; in discussions about the limitations of concepts, Bohr likes to tell the following story; 'A little boy goes into a grocer's shop with a penny in his hand and asks; 'could I have a penny's worth of mixed sweets?' The grocer took out two sweets and handed them to the boy saying; 'here you have two sweets'. You can do the mixing yourself; 'a more serious example of the problematic relation between words and concepts is the fact that words 'red' and 'green' are used even by people who are  colour  blind, though the ranges of applicability of these terms must be quite different for them what they are for other people. The intrinsic uncertainty of the meaning of words was of course recognized very early and has brought the need for definitions, or as the word 'definition' says-for the setting of boundaries that determine where the word is to be used and where not. But definitions can be given only with help of other concepts, and so one will finally have to rely on some concepts that are taken as they are, unanalyzed and undefined. In Greek philosophy the problem of the concepts in language has been a major theme since Socrates, whose life was if we can follow Plato's artistic representation in his dialogues a continuous discussion about the content of the concepts in language and about the limitations in modes of expression. In order to obtain a solid basis for scientific thinking, Aristotle in his logic started to analyze the forms of language, the formal structure of conclusions and deductions independent of their content. In this way, he reached a degree of abstraction and precision that had been unknown up to that time in Greek philosophy and he thereby contributed immensely to the clarification, to the establishment of order in our methods of thought. He actually created the basis for the scientific language.
On the other hand, his logical analysis of language again involves of oversimplification. In logic, the attention is drawn to very special structures, unambiguous connections between premises and deductions. Simple patterns of reasoning and all other structures of language are neglected. These structures may arise from associations between certain meanings of words. For instance, a secondary meaning of a word which only vaguely through the mind when the word is heard may contribute essentially to the content of a sentence. The fact is that every word may cause hail-conscious movements in our mind which can be used to represent some part of reality in the language much more clearly than by the use of logical patterns.

Choose the word which is most nearly the same in meaning as the word printed in bold as used in the passage?
Prehistoric