(immunology) A structure, typically formed on the surface of a pathogen cell membrane as a result of the activation of the host's complement system, creating transmembrane channels that disrupt the cell membrane, leading to cell lysis and death.

(pathology) A transcription disorder that causes failures of expression causing the lack of advancement in development from the state found as a neonatal resulting from genetic anomalies. A developmental disorder that is a state of permanent neoteny, staying in the state of an infant.

(neuroanatomy, anatomy) A collection of brainstem nuclei involved in hearing.

(medicine, pathology) A prodromal phase of infection with the human immunodeficiency virus.

plural of split-complex number

(psychoanalysis) A complex said to develop in men who see women as either saintly "Madonnas" or debased prostitutes, potentially leading to the inability to maintain sexual arousal within a committed, loving relationship.

(psychology) An individual difference (can be thought of as a personality variable) referring to the extent that an individual prefers complex explanations for behavior.

(computer science) the amount of time an algorithm requires to run, as a function of the amount of input, measured in such a way as to ignore constant terms and multiplication by constant terms

(biology, pseudoscience) The proposition that complex organs such as eyes and flagella must have started existing in their current form; i.e., that they cannot have evolved from previous, less complex stages.

(computer science) The study and classification of decision problems by the computational resources—such as time and space—needed by the programs that solve the problems.