The term non-humanoid designated lifeforms which did not share certain morphological, biological, and physiological traits with humanoids and could exist in a wide variety of types.
A nitrogen sulfide atmosphere was considered an indicator of non-humanoid life. (ENT: "Broken Bow")
Relations among humanoid species were considered easier than between a humanoid and a non-humanoid one since those lacked a common point of reference to base communications on. (TNG: "The Ensigns of Command")
Examples of non-humanoid species 
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An example of a non-humanoid lifeform
- Nacene (could assume humanoid form)
- Tholians (ENT: "Future Tense")
- The Q (could assume humanoid form)
- Armus on Vagra II (TNG: "Skin of Evil")
- Gomtuu
- Changeling (could assume humanoid form)
- Crepusculans
- Horta of Janus VI
- Trill symbiont (a vermiform)
- The Crystalline Entity
- Species 8472 (could assume humanoid form)
- Xindi-Arboreals, Xindi-Insectoids and Xindi-Aquatics
