erratic
/ɪˈɹætɪk/adjective
Behaving or happening in an unpredictable, irregular way; lacking any steady pattern.
Example sentences
- “His driving was so erratic that we asked him to pull over.”
- “The patient's heartbeat became erratic during the night.”
Describes driving, behavior, heartbeats, and form in sport. Geologists call a boulder left behind by a glacier an erratic.