1. Consisting of or comprehending various parts united or connected together; formed by combination of different elements; composite, compound. Said of things, ideas, etc. (Opposed to simple, both here and in sense 2.)
2. esp. a. Consisting of parts or elements not simply co-ordinated, but some of them involved in various degrees of subordination; complicated, involved, intricate; not easily analysed or disentangled.complex, n.
1. a. A whole comprehending in its compass a number of parts, esp. (in later use) of interconnected parts or involved particulars; a complex or complicated whole.
3. Psychol. A
group of emotionally charged ideas or mental factors, unconsciously
associated by the individual with a particular subject, arising from
repressed instincts, fears, or desires and often resulting in mental
abnormality; freq. with defining word prefixed, as inferiority, 
dipus
Source: Oxford English Dictionary (Online Ed.)
