The most damaging 1-letter word  : I
Avoid it.
The most satisfying 2-letter word: WE
Use it.
The most poisonous 3-letter word: EGO
Kill it.
The most used 4-letter word : LOVE
Value it.
The most pleasing 5-letter word : SMILE
Wear it.
The most spreading 6-letter word: RUMOR
Ignore it.
The most enviable 7-letter word: SUCCESS
Achieve it.
The most nefarious 8-letter word: JEALOUSY
Distance it.
The most powerful 9-letter word : KNOWLEDGE
Acquire it.
The most essential 10-letter word: CONFIDENCE
Get it and keep it