Idiom Topics
The Ubiquitous Essentials
10- On the other hand
- At the end of the day
- In the long run
- Bear in mind
- A piece of cake
- Keep an eye on
- Out of the blue
- Rule of thumb
- So far, so good
- Behind the scenes
Everyday Casual & Workplace
10- Under the weather
- Call it a day
- Up in the air
- Wrap your head around
- Break the ice
- Get out of hand
- Go the extra mile
- Touch base
- Hit the nail on the head
- Cut corners
Problem Solving & Interaction
10- See eye to eye
- Read between the lines
- Take it with a grain of salt
- Get the hang of it
- Give the benefit of the doubt
- The elephant in the room
- Hit the ground running
- Play it by ear
- Bite the bullet
- Sit on the fence
Decisions & Perspectives
9- Jump on the bandwagon
- Cross that bridge when we come to it
- The best of both worlds
- A blessing in disguise
- Once in a blue moon
- Pull someone's leg
- Miss the boat
- Better late than never
- Get your act together
Colorful & Traditional
10- Spill the beans
- Let the cat out of the bag
- Bite off more than you can chew
- Go back to the drawing board
- Barking up the wrong tree
- Actions speak louder than words
- A penny for your thoughts
- Break a leg
- Hit the sack
- Beat around the bush
Academic & Formal Discourse
10- Bear fruit
- Pave the way
- Shed light on
- Go hand in hand
- Tip the scales
- Fly in the face of
- Bring to the table
- Turn a blind eye
- Draw a blank
- State of the art
Emotions & Reactions
10- Over the moon
- Down in the dumps
- On edge
- Blow off steam
- Keep your cool
- Drive someone up the wall
- On cloud nine
- A weight off my shoulders
- At your wits' end
- Thrilled to bits
Effort, Success, & Failure
10- Start from scratch
- Pass with flying colors
- Fall flat
- Go down the drain
- Keep your head above water
- Pay off
- Throw in the towel
- Make headway
- Uphill battle
- Back to square one
Time, Speed, & Urgency
10- Beat the clock
- At the eleventh hour
- Around the clock
- In the nick of time
- Drag your feet
- Time flies
- Make up for lost time
- Call time on
- Ahead of the curve
- On the spur of the moment
Resources, Money, & Value
10- Make ends meet
- Foot the bill
- Break the bank
- Tighten your belt
- Bang for your buck
- A drop in the ocean
- Make a killing
- On a shoestring budget
- Worth your weight in gold
- Pay top dollar
Rule of thumb
Learn the meaning, origin, and usage of the idiom "Rule of thumb" with five example sentences across different contexts. This idiom is part of ourThe Ubiquitous Essentials collection for PTE and IELTS preparation.
Rule of thumb
A practical, simple, and approximate rule or guiding principle based on experience rather than exact scientific calculation.
History & Origin
The phrase likely originates from ancient trade practices where parts of the human body, such as the thumb's width (roughly equal to an inch), were used as convenient, everyday measurement standards. While a popular modern myth connects it to an old English legal decree allowing domestic abuse, historians have completely debunked this, finding no legal record of such a law. Instead, it has always historically referred to a rough, practical method of estimation used by brewers, bakers, and builders.
Examples
As a general rule of thumb, you should drink about eight glasses of water a day, but listen to your body if you need more.
When putting together the project timeline, a good rule of thumb is to add an extra week as a buffer for unexpected delays.
In economic forecasting, a common rule of thumb dictates that two consecutive quarters of negative GDP growth indicate a recession.
For first-time homebuyers, the standard rule of thumb is to look for a property that costs no more than three times your annual income.
In public relations, our primary rule of thumb is to always prioritize transparency and speed when addressing an unfolding crisis.
Quiz
Which of the following sentences uses the idiom correctly?
A. The architect used a rule of thumb to measure the exact millimeters needed for the microchip casing.
B. When baking bread, a helpful rule of thumb is that if the dough feels too sticky, you should add a tablespoon of flour.
C. To break the machine's strict rule of thumb, you must type in the administrative password.
D. The Supreme Court issued a new rule of thumb that all citizens must legally follow starting next month.