| anchor | embed, sink, fix firmly |
| cement | firmly bring together, unite |
| certainly | firmly, steadfastly, unalterably |
| compact | compound, make up firmly, consolidate |
| confix | fix firmly, fasten, bind |
| constantly | assuredly, firmly, certainly, confidently |
| engraff | deep-rooted, firmly implanted |
| ensconce | secure, establish oneself firmly |
| fast | locked up, firmly bolted |
| fast | tightly, firmly, securely |
| fast | constantly, firmly, steadfastly |
| founded | firmly based, secure, stable |
| grounded | firmly established, deep-rooted, strongly founded |
| hold-fast | firmly grasping |
| infixed | captured, caught, firmly held |
| ingrafted | deep-rooted, firmly implanted |
| ingrafted | closely fastened, firmly fixed |
| seated | firmly placed, fixed |
| settled | deep-rooted, firmly implanted |
| straitly | strictly, firmly, stringently |
| true-fixed | firmly established, immovable, unwavering |