an official statement that tells people what they must or must not do
The school has a strict rule against using phones in class.
Always read the safety rules before using the laboratory equipment.
✦ From Latin regula “straight stick, pattern, law”, via Old French reule, later rule.
a flat strip of wood, metal, or plastic used for measuring or drawing straight lines; a ruler
The architect placed a steel rule on the blueprint to draw a clean edge.
I can’t find my 30-centimetre rule for math class.
to govern or control a country, people, or area
Queen Victoria ruled the British Empire for over 60 years.
No single person should rule forever.
the usual way that something happens; what normally occurs
As a rule, I drink coffee only in the morning.
Punctuality is the rule in her family.
the control or government exercised by a person or group
The country prospered under his peaceful rule.
Foreign rule ended after the revolution.
for a judge or court to make an official legal decision
The court ruled that the new law was unconstitutional.
The referee ruled the goal offside.
to draw straight lines on paper, usually with a ruler
The teacher asked the students to rule margins on each page.
Before sketching, she carefully ruled the canvas.
(informal) to be excellent or the best
That new video game rules!
Her guitar solo totally ruled the concert.
