complication

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. The act of complicating.
2. n. A confused or intricate relationship of parts.
3. n. A factor, condition, or element that complicates.
4. n. Medicine A secondary disease, an accident, or a negative reaction occurring during the course of an illness and usually aggravating the illness.

Century Dictionary and Cyclopedia

1. n. A complex combination or intricate intermingling of things, parts, elements, etc.; especially, a perplexing or incongruous intermixture or combination; a confused complex or complexity: as, a complication of knots in a rope; a complication of ideas, diseases, or misfortunes; the complication of one's affairs with those of another.
2. n. That which renders complex, involved, or intricate; that which causes difficulty, entanglement, or interference; an involved and troublesome or embarrassing state of affairs.
3. n. An entwining or infolding; an embrace.
4. n. In entomology, the manner in which an insect folds its wings when at rest.
5. n. In biology, a process the reverse of growth or development, by which the heterogeneous tends toward homogeneity. Synonyms Complication, Complexity. These words are rarely used synonymously. Complication commonly implies entanglement resulting either in difficulty of comprehension or in embarrassment; complexity, the multiplicity and not easily recognized relation of parts: as, business complications; the complexity of a machine; the complexity of a question of duty. See intricate.
6. n. In psychology, the simultaneous association of perceptions or ideas of different senses.

Wiktionary

1. n. The act or process of complicating; the state of being complicated; intricate or confused relation of parts; entanglement; complexity.
2. n. A person who doesn't fit in with the main scheme of things; an interloper; someone you need to placate.
3. n. medicine A disease or diseases, or adventitious circumstances or conditions, coexistent with and modifying a primary disease, but not necessarily connected with it.
4. n. A feature beyond basic time display in a timepiece.

GNU Webster's 1913

1. n. The act or process of complicating; the state of being complicated; intricate or confused relation of parts; entanglement; complexity.
2. n. (Med.) A disease or diseases, or adventitious circumstances or conditions, coexistent with and modifying a primary disease, but not necessarily connected with it.

WordNet 3.0

1. n. puzzling complexity
2. n. a situation or condition that is complex or confused
3. n. any disease or disorder that occurs during the course of (or because of) another disease
4. n. the act or process of complicating
5. n. a development that complicates a situation