alcohol

you can say "both", depending on the other reactant.

commonly, alcohol is reducing where itself is oxidized.
for example, alcohols (primary like methanol, ethanol, propan-1-ol & benzyl alcohol; or secondary like propan-2-ol) can be oxidized by acidified dichromate to give aldehydes/ketones (respectively methanal, ehtanal, propanal, benzaldehyde & propanone).

ethanol:
CH3CH2OH + [O] ------> CH3CHO + H2O + 2e-
or CH3CH2OH ------> CH3CHO + 2H(+) + 2e-

propan-2-ol:
CH3CH(OH)CH3 ------> CH3C(=O)CH3 + 2H(+) + 2e-

benzyl alcohol:
C6H5-CH2OH ------> C6H5-CHO + 2H(+) + 2e-

Cr2O7(2-) + 14H(+) + 6e- ------> 2Cr(3+) + 7H2O

(you can balance the equation yourself)

in these reactions, alcohol is oxidized by dichromate -- in other words, dichromate is reduced by alcohols. product is alkanal / alkanone.


on the other hand, alcohol can also act as oxidizing agent.
for example, sodium metal can react with ethanol to give sodium ethoxide + hydrogen gas.
the hydrogen in R-OH is reduced by sodium to give H2; sodium is oxidized by hydrogen in R-OH to give sodium ion.

2Na + 2C2H5OH ------> 2C2H5ONa + H2

in some laboratories doing synthesis, alkali metals like sodium is disposed / destroyed by reaction with alcohols, followed by careful addition of water for dilution, and/or neutralization by acids before flushing away.