I just found this wonderful essay on the etymology of meditation at answers.com
Meditation: Etymology and history
Main article: History of meditation
Caravans on the Silk Road helped spread meditative practices from India.
The word meditate stems from the Latin root meditatum, i.e. to ponder. In the Old Testament hāgâ (Hebrew: הגה), means to sigh or murmur, but also to meditate. When the Hebrew Bible was translated into Greek, hāgâ became the Greek melete. The Latin Bible then translated hāgâ/melete into meditatio. The use of the term meditatio as part of a formal, stepwise process of meditation goes back to the 12th century monk Guigo II.
Apart from its historical usage, the term meditation was introduced as a translation for Eastern spiritual practices, generally referred to as dhyāna, which comes from the Sanskrit root dhyai, meaning to contemplate or meditate. The term "meditation" in English may also refer to practices from Islamic Sufism, or other traditions such as Jewish Kabbalah and Christian Hesychasm. A recent edited book about "meditation", for example, included chapter contributions by authors describing Buddhist, Christian, Hindu, Islamic, and Taoist traditions. Scholars have noted that "the term 'meditation' as it has entered contemporary usage" is parallel to the term "contemplation" in Christianity.
It is difficult to trace the history of meditation without considering the religious context within which it was practiced. Data suggest that even at prehistoric times older civilizations used repetitive, rhythmic chants and offerings to appease the gods. Some authors have even suggested the hypothesis that the emergence of the capacity for focused attention, an element of many methods of meditation, may have contributed to the final phases of human biological evolution. References to meditation with Rishabha in Jainism go back to the prehistoric age with the Acaranga Sutra dating to 500 BC.. Some of the earliest written records of meditation date to 1500BC in Hindu Vedantism. Around 500-600BC Taoists in China and Buddhists in India began to develop meditative practices.
In the west, by 20BCE Philo of Alexandria had written on some form of "spiritual exercises" involving attention (prosoche) and concentration and by the 3rd century Plotinus had developed meditative techniques, which however did not attract a following among Christian meditators.
The Pāli Canon, which dates to 1st century BCE considers Indian Buddhist meditation as a step towards salvation. By the time Buddhism was spreading in China, the Vimalakirti Sutra which dates to 100CE included a number of passages on meditation, clearly pointing to Zen. The Silk Road transmission of Buddhism introduced meditation to other oriental countries, and in 653 the first meditation hall was opened in Japan,. Returning from China around 1227, Dōgen wrote the instructions for Zazen.
The Islamic practice of Dhikr had involved the repetition of the 99 Names of God in the Qur'an since the 8th or 9th century. By the 12th century, the practice of Sufism included specific meditative techniques, and its followers practiced breathing controls and the repetition of holy words. Interactions with Indians or the Sufis may have influenced the Eastern Christian meditation approach to hesychasm, but this can not be proved. Between the 10th and 14th centuries, hesychasm was developed, particularly on Mount Athos in Greece, and involves the repetition of the Jesus prayer.
Western Christian meditation contrasts with most other approaches in that it does not involve the repetition of any phrase or action and requires no specific posture. Western Christian meditation progressed from the 6th century practice of Bible reading among Benedictine monks called Lectio Divina, i.e. divine reading. Its four formal steps as a "ladder" were defined by the monk Guigo II in the 12th century with the Latin terms lectio, meditatio, oratio, and contemplatio (i.e. read, ponder, pray, contemplate). Western Christian meditation was further developed by saints such as Ignatius of Loyola and Teresa of Avila in the 16th century.
By the 18th century, the study of Buddhism in the West was a topic for intellectuals. The philosopher Schopenhauer discussed it, and Voltaire asked for toleration towards Buddhists. The first English translation of the Tibetan Book of the Dead was published in 1927.
Secular forms of meditation were introduced in India in the 1950s as a Westernized form of Hindu meditative techniques and arrived in the United States and Europe in the 1960s. Rather than focusing on spiritual growth, secular meditation emphasizes stress reduction, relaxation and self improvement. Both spiritual and secular forms of meditation have been subjects of scientific analyses. Research on meditation began in 1931, with scientific research increasing dramatically during the 1970s and 1980s. Since the beginning of the '70s more than a thousand studies of meditation in English-language have been reported. However, after 60 years of scientific study, the exact mechanism at work in meditation remains unclear.