| inactive(adjective, still, passive, motionless, stationary) |
| incessant(adjective, steady, regular, persistent, even) |
| inert(adjective, still, passive, motionless, stationary) |
| intense(adjective, firm, solid, stable, fixed) |
| interminable(adjective, persistent, continuous, endless, relentless) |
| invariant(adjective, even) |
| level-headed(adjective, calm, smooth, steady, temperate) |
| levelheaded(adjective, firm, solid, stable, fixed) |
| liege(adjective, firm, solid, stable, fixed) |
| loyal(adjective, firm, solid, stable, fixed) |
| methodical(adjective, calm, smooth, steady, temperate) |
| never-failing(adjective, firm, solid, substantial, stable) |
| neverending(adjective, stable, regular, persistent, continuous) |
| obstinate |
| orderly(adjective, calm, smooth, steady, temperate) |
| passive(adjective, still, motionless, stationary, changeless) |
| patterned(adjective, firm, solid, substantial, stable) |
| persisting(adjective, persistent, continuous, endless, relentless) |
| phlegmatic(calm, composed, unflappable) |
| placid(adjective, calm, smooth, steady, temperate) |