Synonyms for Seamless (same or very similar meaning)
WordNet sense 1 (having no seams):
unseamed
WordNet sense 2 (used especially of skin):
unlined
WordNet sense 3 (having a surface free from roughness or bumps or ridges or irregularities):
smooth
WordNet sense 4 (marked by an orderly, logical, and aesthetically consistent relation of parts):
coherent, consistent, logical, ordered, orderly
From the ODE community, based on WordNet
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