What is the meaning of Roer?

A rifle, a gun.

A rudder.

to gnaw (to bite something persistently)

rower

oarsman, oarswoman

indefinite plural of roe (“beet, rutabaga, turnip”)

a boat's wheel

a rudder, device to steer a vessel

(used absolutely, with the definite article: het roer) control

light musket, matchlock gun

inflection of roeren:

1. first-person singular present indicative
2. (in case of inversion) second-person singular present indicative
3. imperative

first-person singular present indicative

(in case of inversion) second-person singular present indicative

imperative

to gnaw, to nibble, to bite

to corrode

an oarsman, rower

present of roe

to gnaw

to gnaw

to pick at

to wear down

Source: wiktionary.org