Hello, my w2 has in box 14 something called ORSTTWA with an amount next to it....does anyone know what it stands for?

ORSTT Wages = ORegon Statewide Transit Tax Wages.

ORSTT W/H = ORegon Statewide Transit Tax WitHolding

https://www.oregon.gov/DOR/programs/businesses/pages/statewide-transit-tax.aspx 

Additional info:

1) IF the $$ amount is close to your  Oregon wages (after 1 July 2018), then choose "Other not on above list" for it's tax category  (There is some debate as to whether "wages" should even be included in box 14)

2) If the amount is obviously a smaller tax value...then choose "OR STT W/H'" for it's Tax Category if you are using the Online browser-based tax software.  (should be ~ 0.1% of your OR wages after 1 July 2018)