complex, complicated, intricate...

plural, multiple, plural (number)

composite, combined, complex

compound, composite, multiple...

copying, duplication, reproduction...

duplication, repetition, overlapping...

republication, reissue, reprinting...

reproduction, duplication, reprinting

compound interest

complexity

facsimile edition, reprint

double track, two-track line

compound eye

double-entry (e.g. bookkeeping)

simplicity and complexity, singular and plural, single and double...

photocopier, photocopying machine

duplicate, copy

double vision, polyopia

complex sentence, sentence with an independent clause and at least one dependent clause

compound drug

compound note (on a harmonica)

two-seater (e.g. aircraft)

two-seater (e.g. aircraft)

compound leaf, biplane

placing bets

lined garment

multiple star

duopoly

polygamy

double salt