1. making or becoming less dense; thinning out
Usage: present participle of rarefy
2. making something more refined or elevated in character
Usage: formal; present participle of rarefy

Examples

• The air is rarefying as we climb higher up the mountain.
• Heat was rarefying the gas in the chamber.
• The atmosphere is rarefying at this altitude.
• The artist spent years rarefying his technique.
• Education has a rarefying effect on one’s perspective.
• The balloon expanded as the air inside was rarefying.