In his communication a scientist is mainly concerned with exact and logical expression of that which he wishes to pass on to another. His purpose is to inform as clearly as possible. Each of his words must have a precise meaning and one meaning only so that there is no risk of confusion or ambiguity. The meanings of many ordinary words of our language are not single and precise. The use of words which are ‘set apart’ from everyday life also enables the scientist to avoid evoking irrelevant and distorting associations.
In addition to precision of meaning and freedom from associations most scientific words by their form and structure they reveal something of their meanings. Many scientific words are built from simpler word-elements usually of Greek origin. Some words are self-explanatory if the Greek roots are known.
Scientific language to be efficient must be universally intelligible. The classical language Greek is so fundamental to the civilised world. The words constructed from this language can easily be learnt to be translated.
So scientific terms use Greek words.