In this subtitle:
(1) "Official traffic-control device" means a sign, signal, marking, or device that is:
(A) consistent with this subtitle;
(B) placed or erected by a public body or officer having jurisdiction; and
(C) used to regulate, warn, or guide traffic.
(2) "Railroad sign or signal" means a sign, signal, or device erected by a railroad, public body, or public officer to notify traffic of railroad tracks or an approaching railroad train.
(3) "Traffic-control signal" means a manual, electric, or mechanical device that alternately directs traffic to stop and to proceed.