Arabic language is vastly inflected, thus the process of effective Arabic text analysis with correct stem and root extraction is challenging. In this paper we present a linguistic root extraction approach that is composed of two main phases. In the first phase we handle removal of affixes including prefixes, suffixes and infixes. Prefixes and suffixes are removed depending on the length of the word, while checking its morphological pattern after each deduction to remove infixes. In the second phase, the root extraction algorithm is developed further to handle weak, hamzated, eliminated-long-vowel and two-letter geminated words as there is a rationally great amount of irregular Arabic words in texts. Before roots are extracted, they are checked against a predefined list of 3800 triliteral and 900 quad literal roots. Series of experiments has been conducted to improve and test the performance of the proposed algorithm. The obtained results revealed that the roots are extracted correctly has improved comparing with Khoja's stemming algorithm.