| firmly(adverb, stably, inelastically) |
| fast(adjective, adverb, thoroughly, strongly, firmly) |
| rigidly(adverb, thoroughly, strongly, firmly, definitely) |
| steadily(adverb, strongly, firmly, definitely, resolutely) |
| inflexibly(adverb, thoroughly, strongly, firmly, definitely) |
| solidly(adverb, thoroughly, strongly, firmly, definitely) |
| steadfastly(adverb, stably) |
| constantly(adverb, stably) |
| securely(adverb, thoroughly, strongly, firmly, definitely) |
| stably(adverb, thoroughly, strongly, firmly, definitely) |
| consistently(adverb, stably) |
| durably(adverb, thoroughly, strongly, firmly, definitely) |
| fixedly(adverb, thoroughly, strongly, firmly, definitely) |
| motionlessly(adverb, thoroughly, strongly, firmly, definitely) |
| permanently(adverb, stably) |
| persistently(adverb, stably) |
| stiffly(adverb, thoroughly, strongly, firmly, definitely) |
| tightly(adverb, thoroughly, strongly, firmly, definitely) |
| unalterably(adverb, inelastically) |
| unmovedly |