| habitual(adjective, dull, steady, stable, regular) |
| invariable(adjective, smooth, solid, level, true) |
| lasting(adjective, persistent, constant, continuous, endless) |
| perennial(adjective, continuous) |
| regular(adjective, dull, direct, steady, stable) |
| repeated(adjective, continuous) |
| seamless(adjective, continuous) |
| timeless(adjective, continue) |
| unchanging(adjective, steady, stable, regular, fixed) |
| unvarying(adjective, dull, steady, stable, regular) |
| without pause |
| beeline(adjective, adverb, smooth, right, solid) |
| consistent(adjective, dull, steady, stable, regular) |
| dateless |
| express(adjective, direct, fast, straight, rapid) |
| homogeneous(adjective, dull, steady, stable, regular) |
| nonstop flight(noun, expression, idiom) |
| ongoing(adjective, continue) |
| relentlessly(adverb, continually, incessantly, unceasingly, uninterruptedly) |
| running |