well-defined (adj.)

• clean-cut
• clear
• clear-cut
• coherent
• connected
• consistent
• conspicuous
• crisp
• crystalline
• defined
• definite
• direct
• distinct
• evident
• explicit
• express
• glaring
• limpid
• lucid
• luminous
• obvious
• patent
• pellucid
• perspicuous
• plain
• prominent
• pronounced
• simple
• staring
• straightforward
• translucent
• transparent
• unambiguous
• unconfused
• unequivocal
• univocal
• unmistakable
• well-marked