motif

noun

• 1a decorative image or design, especially a repeated one forming a pattern:the colourful hand-painted motifs which adorn narrowboats
• a decorative device applied to a garment or textile: floral or other motifs are then appliquéd to net veils

• 2a dominant or recurring idea in an artistic work:superstition is a recurring motif in the book
• Music a leitmotif or figure (see figure (sense 5 of the noun)): in this opera, Verdi used identifying motifs

• 3 Biochemistry a distinctive sequence on a protein or DNA, having a three-dimensional structure that allows binding interactions to occur.