| persistent(adjective, strain, firmness, constant, continuous) |
| firm(adjective, strain, firmness, persistent, continuous) |
| stable(adjective, strain, firmness, persistent, continuous) |
| consistent(adjective, strain, firmness, persistent, continuous) |
| unfluctuating(adjective, strain, firmness, persistent, continuous) |
| constant(adjective, strain, firmness, persistent, continuous) |
| lasting(adjective, great, strain, deep, high) |
| perpetual(adjective, strain, firmness, persistent, constant) |
| steady(adjective, strain, firmness, persistent, continuous) |
| enduring(adjective, great, strain, deep, high) |
| steadfast(adjective, strain, firmness, persistent, continuous) |
| permanent(adjective, strain, firmness, persistent, continuous) |
| durable(adjective, strain, firmness, labour, hardiness) |
| quiescent(adjective, strain, firmness, labour, hardiness) |
| rigid(adjective, strain, firmness, labour, hardiness) |
| stationary(adjective, strain, firmness, labour, hardiness) |
| staying(adjective, strain, firmness, labour, hardiness) |
| unyielding(adjective, strain, firmness, labour, hardiness) |
| lingering(adjective, great, strain, slow, deep) |
| invariable(adjective, strain, firmness, persistent, continuous) |