Since the prefix "im-" literally means "not", it follows that whatever is "not material" is literally "immaterial"*1. Yet apparently, those not-matter words have an unplatable implication for you. Perhaps, to you "immaterial" is equated with "unreal" or "spiritual", and "material" means "real" or "mundane". If so, your definition of "material" is even more metaphysical*2 than mine. Instead of those spooky notions though, I'm thinking in terms of reductive/pluralistic scientific categories, in which massive Matter is merely a condensed form of ethereal Energy (E=MC^2), or ultimately of elucidating Light.
In the metaphysics of Materialism, both tangible things and conceptual processes are included under the umbrella of Physicalism or Realism. Yet, physical scientists routinely make a distinction between Matter and processes affecting material objects. For example, Matter (mass) has inertia, and does not change position unless acted upon by some outside Force. But what substance is a force made of? For scientists, a Force is a type of Energy acting upon Matter*3. Ironically, The ancient philosophy of Materialism, led 18th century scientists to imagine Energy as a material substance : Phlogistion*4. But today, Energy (causation) is accepted as an immaterial & non-mechanical influence on matter (spooky action at a distance).
Materialism is a monistic doctrine*5, based on evidence of the physical senses. But my personal Enformationism worldview is also monistic, and based on the non-physical (immaterial) element of the real world that we know in various forms, such as Energy or Mind or Reason. According to Materialism, the Mind must be material. But that presumption leads to the philosophical Mind/Body Problem. Yet, if you assume that Generic Information is the basic element of the world, the "problem" vanishes as you look at it from a new perspective : Information Physics*6. I won't go into the details of that worldview here. I'll just mention that it's a novel form of Metaphysical Monism.
*1. A Prefix 'im' is used in the following two situations: Meaning not or no: when the prefix 'im' is used with some adjectives and nouns that begin with b, m, or p, it states the opposite meaning. For example immortal, immature, imperfect, etc.
https://theglobalmontessorinetwork.org/ ... m-english/
*2. Metaphysical : referring to an idea, doctrine, or posited reality outside of human sense perception. In modern philosophical terminology, metaphysics refers to the studies of what cannot be reached through objective studies of material reality. ___Wiki
*3. In physics, a force is an influence that causes the motion of an object with mass to change its velocity i.e., to accelerate. ___Wiki
Note -- Influence comes in many immaterial forms, from physical forces to social influences.
*4. Phlogiston, in early chemical theory, hypothetical principle of fire, of which every combustible substance was in part composed. In this view, the phenomena of burning, now called oxidation, was caused by the liberation of phlogiston, with the dephlogisticated substance left as an ash or residue.
https://www.britannica.com/science/phlogiston
*5. Materialism is a form of philosophical monism which holds matter to be the fundamental substance in nature, and all things, including mental states and consciousness, are results of material interactions of material things. ___Wikipedia
*6. Information physics, which is based on understanding the ways in which we both quantify and process information about the world around us, is a fundamentally new approach to science.
https://arxiv.org/abs/1009.5161
Note -- 21st century scientists now posit Information as the fundamental element of reality.
https://www.pbs.org/wgbh/nova/article/i ... ndamental/