| habitual(adjective, dull, steady, stable, regular) |
| homogeneous(adjective, dull, steady, stable, regular) |
| horizontal(adjective, calm, direct, smooth, right) |
| identical(adjective, calm, smooth, flat, plain) |
| immovable(adjective, strong, secure, firm, solid) |
| imperturbable(adjective, calm, smooth, firm, solid) |
| in line(expression, adjective, calm, smooth, flat) |
| incorrigible(adjective, normal, even, rigid, inflexible) |
| inflexible(adjective, fixed, normal, even, constant) |
| irreversible(adjective, normal, even, rigid, inflexible) |
| latent(adjective, still, passive, motionless, stationary) |
| leveled(adjective, calm, smooth, flat, plain) |
| like(adjective, calm, smooth, flat, plain) |
| like the Rock of Gibralter(expression, adjective, idiom, steady, stable) |
| lined up(expression, adjective, calm, smooth, flat) |
| matched(adjective, calm, smooth, flat, plain) |
| matching(adjective, calm, direct, smooth, right) |
| methodical(adjective, calm, smooth, steady, temperate) |
| monochrome(adjective, dull, steady, stable, regular) |
| monolithic(adjective, normal, even, rigid, inflexible) |