The syllable sid is one of the most fascinating and mysterious in the history of Indo-European languages. It hides a deep connection between the concept of light, starry sky and personal fulfilment. In this article, we will rely on the research of the Italian linguist Franco Rendich, author of an innovative comparative etymological dictionary of the classical Indo-European languages, to explore the origins and transformations of this syllable in the different languages. We will see how the sid syllable has gone from the meaning of “tying oneself to the motion of light” in Indo-European, to that of “fulfilment” in Sanskrit, to that of “constellation” in Latin. We will also discover how two fundamental verbs for human psychology and philosophy have derived from this syllable: I desire and I consider.
The Indo-European origin: sidh [si+dh]
According to Rendich’s theory, the sid syllable derives from an Indo-European verbal root composed of two elements: si and dh. The first element, si, means “to tie”, “to join”, “to be connected”. The second element, dh, indicates motion, dynamism, and vital force. Together, these two elements form the meaning of “tying oneself to the motion of light”, “being successful”, “fulfilling oneself”, and “reaching perfection”.
This verbal root thus expresses an ideal of life, an aspiration to achieve the fullness of one’s being, in harmony with nature and the cosmos. It has a very deep and spiritual meaning, reflecting the worldview of the ancient Indo-European peoples, who believed in a unitary and dynamic reality, governed by a universal law and a creative force.
The Sanskrit derivation: siddha, siddhānta, siddhi, Siddhârtha
Sanskrit, the sacred language of ancient India, preserves the sid syllable in many terms reflecting its Indo-European origin. The verb sidh, sidhyati means “to succeed”, “to be fulfilled”, “to accomplish”. Various nouns derive from it expressing the concept of fulfillment in different areas. Siddha means “fulfilled”, “accomplished”, and “perfect”. Siddhānta means “doctrine of fulfilment”, “dogma”, or “axiom”. Siddhi means “fulfilment”, “success”, and “power”. These terms are used especially in the context of Indian philosophy and religion, particularly Buddhism and Hinduism, to indicate the state of spiritual enlightenment, supreme knowledge, and superhuman abilities. A famous example is the name Siddhârtha, which means “he who has attained his goal”, or “he who shows the path of success and fulfilment”. This is the original name of Gautama Buddha, the founder of Buddhism. The name Siddhârtha encapsulates the meaning of the life and mission of this great spiritual teacher, who taught men the path of liberation from suffering and ignorance.
The Latin transformation: sidus, sideralis, sidereus, desidero, desiderium, considero
Latin, the mother tongue of Roman culture and Romance languages, presents a phonetic variation of the sid syllable: it becomes sidus, with the addition of a final vowel u. This vowel could be due to Etruscan influence, which had a preference for closed syllables. The meaning of sidus, however, is not that of “success” or “fulfilment”, but of “constellation”, “stars”, or “starry sky”. How to explain this change?
According to Rendich, it is an astral metaphor, based on the observation of the night sky. The stars are the sources of light par excellence, and their regular and harmonious movement represents the model of perfection and cosmic order. Furthermore, the stars are associated with divinity, fortune and destiny. For ancient peoples, gazing at the stars was a way to seek the guidance of the gods, to know the future, and to express one’s desires.
From sidus various adjectives are derived that qualify what is related to the stars: sideralis, “of the heavenly bodies”, “sidereal”; sidereus, “starry”. From sidus two very important verbs for human psychology and philosophy also derive desidero and considero. The verb desidero means “to feel the absence of the starry sky”, “to want to see the starry sky”, or “to desire”. It expresses the feeling of longing, aspiration, and yearning for something beautiful, great, distant. The verb considero means “to attune oneself to the starry sky”,” to observe the starry sky”, and “to consider”. It expresses the attitude of reflection, analysis, and rational evaluation of a situation or problem. Both verbs imply attention to the sky, to the stars, to the light. They show how the sid syllable has become a symbol of man’s emotional and cognitive dimension.
The sid syllable is an example of how an Indo-European verbal root can generate a variety of terms in different languages while maintaining or transforming its original meaning. The sid syllable speaks of a link between man and light, between success and stars, between desire and consideration. It invites us to reflect on our relationship with the cosmos, with nature, with ourselves. It reminds us that personal fulfilment is a dynamic process that requires commitment, passion, and wisdom. It suggests to us that light is the goal, but also the guide, of our life.
Here is a simplified conclusion explaining the connection between stars and success, explicitly mentioning the word “success”:
The syllable sid shows how stars and success are linked. Originally, sid meant “tying oneself to moving light” — connecting with the bright sun’s motion. Later, sid became the Latin word sidus, meaning “constellation” — tying to star groups instead of the sun.
So this simple syllable traces an evolution from the sun to stars, joining the ideas of success and the sky’s lights. Throughout history, stars have symbolized meaningful guides, goals, and ideals. The sid syllable reminds us that reaching our personal “success” — accomplishing our aims and full potential — is inspired by the skies above. Just as stars have motivated the creation of myths and imagination over time, they encourage us to strive and shine today. The twinkling sid suggests stars can fuel our efforts to become our best selves — fulfilling our bright success.
Source: Rendich, Franco. “Dizionario etimologico comparato di Indoeuropeo Sanscrito Greco Latino”. Palombi, 2010.