Does anyone know box 14 code means

Box 14 is used by employers only.   If the code or description is not shown in the dropdown for box 14 then just select Other (not classified) at the bottom of the dropdown list.

As stated on the back of the W-2 -

Box 14. Employers may use this box to report information such as state disability insurance taxes withheld, union dues, uniform payments, health insurance premiums deducted, nontaxable income, educational
assistance payments, or a member of the clergy’s parsonage allowance and utilities. Railroad employers use this box to report railroad retirement (RRTA) compensation, Tier 1 tax, Tier 2 tax, Medicare tax, and Additional Medicare Tax. Include tips reported by the employee to the employer in railroad retirement (RRTA) compensation.