Learn how to use the comparative “rarer” and superlative “rarest” with example sentences and differences.

What is the comparative form of “rarefactive”?

The comparative form of “rarefactive” is “rarer”.

Example

The blue diamond is rarer than the white diamond.

Example

Finding a four-leaf clover is rarer than finding a regular clover.

What is the superlative form of “rarefactive”?

The superlative form of “rarefactive” is “rarest”.

Example

Among all the gemstones, the red diamond is the rarest.

Example

The albino peacock is considered one of the rarest birds.

Why is this expression not used with most, more?

'Most' and 'more' are generally not used with rare, rarer, and rarest. They’re considered regular comparatives and superlatives. The forms 'more rare' and 'most rare' are not used because they sound awkward. Instead, rarer and rarest are the correct and preferred forms to use.

Does this expression have an irregular comparative/superlative form?

Rare does not have an irregular comparative or superlative form. It follows the standard pattern for forming comparatives and superlatives. So, to summarize: Comparative: Rare → Rarer Superlative: Rare → Rarest

Expressions with similar meanings to “rarer”

more uncommon

Used to describe something that is less common or less frequently found

Example

Spotting a shooting star is more uncommon than seeing a rainbow.

less frequent

Indicates something that occurs with less frequency or regularity

Example

Snowfall in this region is less frequent compared to other areas.

scarcer

Describes something that is in short supply or hard to find

Example

During the pandemic, toilet paper became scarcer than gold.

Expressions with similar meanings to “rarest”

most uncommon

Similar to rarest, this emphasizes something that is extremely uncommon or rarely found

Example

The sighting of a black swan is considered the most uncommon event.

least frequent

Used to describe something that occurs with the lowest level of frequency or regularity

Example

In this region, tornadoes are the least frequent natural disaster.

most scarce

Describes something that is in the shortest supply or hardest to find

Example

Clean drinking water is the most scarce resource in some parts of the world.

Using than with comparative “rarer”

When using the comparative form rarer to compare two things, you would use than to connect the two parts of the comparison: Example: "The blue diamond is rarer than the white diamond." Here, than is used to show that the rarity of the blue diamond is greater than the rarity of the white diamond.

How can I use this expression in context?

“rarer” and “rarest” can be used in a variety of situations to compare speed.

• 1. Gemstones

  The pink diamond is rarer than the yellow diamond.

  The pink diamond is rarer than the yellow diamond.

• 2. Species

  The endangered tiger is one of the rarest animals on Earth.

  The endangered tiger is one of the rarest animals on Earth.

• 3. Phenomena

  A double rainbow is rarer than a single rainbow.

  A double rainbow is rarer than a single rainbow.

• 4. Events

  Winning the lottery is one of the rarest occurrences in life.

  Winning the lottery is one of the rarest occurrences in life.

• 5. Artifacts

  Ancient artifacts are becoming rarer as time goes on.

  Ancient artifacts are becoming rarer as time goes on.