| durable(adjective, strain, stable, firmness, stability) |
| fast(adjective, strain, firmness, labour, hardiness) |
| stationary(adjective, strain, firmness, labour, hardiness) |
| immutable(adjective, calm, strong, secure, firm) |
| fixed(adjective, severe, harsh, solid, ordinary) |
| seamless(adjective, strain, firmness, uniform, continuous) |
| settled(adjective, strain, firmness, labour, hardiness) |
| unchangeable(adjective, calm, strong, secure, firm) |
| unyielding(adjective, strain, firmness, labour, hardiness) |
| long-standing(adjective, strain, firmness, labour, hardiness) |
| stabile(adjective, calm, strong, secure, strain) |
| stout(adjective, strain, firmness, labour, hardiness) |
| substantial(adjective, strain, firmness, labour, hardiness) |
| changeless(adjective, change, severe, harsh, solid) |
| non-fluctuating(adjective, strain, firmness, labour, hardiness) |
| refractory(adjective, strain, firmness, labour, hardiness) |
| sustained(adjective, strain, firmness, persistent, continuous) |
| uniform(adjective, calm, quiet, strong, secure) |
| well-balanced(adjective, strain, firmness, even, labour) |
| regular(adjective, quiet, soft, gentle, flat) |