An accredited investor is someone who meets SEC-defined income, net worth, or professional-knowledge thresholds that legally qualify them to invest in unregistered securities, like startup equity, without the disclosures required for a public offering.
The traditional thresholds are a net worth over $1 million excluding a primary residence, or income over $200,000 individually ($300,000 with a spouse) in each of the last two years. More recent rules also let people qualify based on certain professional certifications or knowledgeable-employee status, regardless of income or net worth.
This status exists to protect less sophisticated investors from the higher risk of unregistered private investments, and it's why most startup fundraising is legally restricted to accredited investors rather than open to anyone who wants to write a check. A company raising money is generally responsible for confirming accreditation, not just taking an investor's word for it.
Add your revenue and website for a full diligence brief, reviewed by a CPA who ran EY's West Coast R&D Tax Credit practice for 13 years.