strengthening (n.)
- accelerando
- acceleration
- affirmation
- aggravation
- analeptic
- attestation
- authentication
- backing
- blowup
- bracing
- buttressing
- certification
- concentration
- condensation
- confirmation
- consolidation
- corroboration
- deepening
- documentation
- enhancement
- exacerbation
- exaggeration
- explosion
- fortification
- hardening
- intensification
- invigoration
- magnification
- pickup
- proof
- proving
- ratification
- refreshment
- reinforcement
- restorative
- revivification
- speedup
- step-up
- substantiation
- support
- tempering
- tightening
- tonic
- validation
- verification
