1. spiritual beings believed to serve as messengers of God or to guard and guide humans
Usage: religious context
2. people who are very kind, helpful, or good
Usage: figurative use
3. financial backers who provide funding for business ventures, especially startups
Usage: business context; informal

Examples

• The children dressed as angels for the Christmas play.
• Many people believe that guardian angels watch over them.
• She was an angel to help me move all my furniture.
• The startup received funding from several angel investors.
• Angels are often depicted with wings and halos in religious art.
• You’re such an angel for bringing me soup when I was sick.
• The company is seeking angels to invest in their new technology.