1099 NEC is Non Employee Compensation. It was split off from form 1099Misc box 7.
1099NEC & 1099Misc Instructions
https://www.irs.gov/pub/irs-pdf/i1099mec.pdf
1099NEC https://www.irs.gov/pub/irs-pdf/f1099nec.pdf
1099Misc https://www.irs.gov/pub/irs-pdf/f1099msc.pdf
