seamless (adj.)

• articulated
• ceaseless
• connected
• constant
• continual
• continued
• continuing
• continuous
• cyclical
• direct
• endless
• featureless
• immediate
• incessant
• interminable
• joined
• linked
• monotonous
• never-ending
• nonstop
• perennial
• periodic
• recurrent
• repetitive
• round-the-clock
• running
• serried
• smooth
• stable
• steady
• straight
• unbroken
• unceasing
• undifferentiated
• unending
• uniform
• uninterrupted
• unrelieved
• unremitting