Dic: intricate

LDOCE: containing many small parts or details that all work or fit together

American Heritage:

1. Having many complexly arranged elements; elaborate. (See Synonyms at elaborate)
2. Solvable or comprehensible only with painstaking effort. (See Synonyms at complex )

Roget II Thesaurus:

1. Difficult to understand because of intricacy (byzantine, complex, complicated, convoluted, daedal, Daedalian, elaborate, involute, involved, knotty, labyrinthine, tangled.) See SIMPLE.
2. Complexly detailed (complicated, elaborate, fancy.) See PLAIN.

* * *

Synonyms: complex, complicated, intricate, involved, tangled, knotty

These adjectives mean having parts so interconnected as to make the whole perplexing.

• Complex implies a combination of many associated parts:
   ... The composer transformed a simple folk tune into a complex set of variations.
• Complicated stresses elaborate relationship of parts:
   ... The party's complicated platform confused many voters.
• Intricate refers to a pattern of intertwining parts that is difficult to follow or analyze:
   ... "No one could soar into a more intricate labyrinth of refined phraseology" (Anthony Trollope). 
• Involved stresses confusion arising from the commingling of parts and the consequent difficulty of separating them:
   ... The movie's plot was criticized as being too involved.
• Tangled strongly suggests the random twisting of many parts:
   ... "Oh, what a tangled web we weave,/When first we practice to deceive!" (Sir Walter Scott).
• Knotty stresses intellectual complexity leading to difficulty of solution or comprehension:
   ... Even the professor couldn't clarify the knotty point.

....... American Heritage