rational

Pluralrationals

1. 1
   adjective

   Thinking in a clear, calm, and sensible way.

   Like keeping a clear head when everyone around you is panicking.

   After a good night's sleep, she felt calm and rational again.

   He stayed rational even when everyone around him panicked.

   Similarsane, sensible, reasonable, level-headed, lucid

   Oppositeirrational, unreasonable

   Note
2. 2
   adjective

   Able to think things through and use reason.

   Like a person who works out a puzzle one clue at a time.

   Humans are rational and can solve hard problems together.

   Many people believe only rational beings can plan for the future.

   Similarintelligent

   Oppositeirrational

   Note
3. 3
   adjective

   Based on clear logic, with no parts that disagree with each other.

   Like a plan where all the parts fit together without clashing.

   Her argument was rational and easy to follow.

   They wanted a rational plan, not a wild guess.

   Similarlogical, reasonable, sound, coherent, sensible

   Oppositeirrational, illogical, absurd

4. 4
   adjective

   Able to be written as one whole number divided by another.

   Like cutting a cake into equal parts you can name with a fraction.

   One half is a rational number because it equals 1 divided by 2.

   The fraction three-quarters is rational.

   Oppositeirrational

   Note
5. 5
   nouncountable

   A number you can write as one whole number divided by another.

   Like any amount you could write neatly as a fraction.

   One half is a rational.

   You can write any rational as a fraction.

   Oppositeirrational

   Note
6. 6
   adjective

   Able to be written as one polynomial divided by another.

   The expression (x+1)/(x-2) is rational.

   A rational function is just one polynomial divided by another.

   Note
7. 7
   adjective

   Of a shape in advanced math, simple nearly everywhere and like a basic flat space.

   Mathematicians proved that the surface is rational.

   A rational variety looks simple over almost all of its points.

   Note
8. 8
   adjective

   Of a map between shapes in advanced math, working smoothly on an open part of where it is defined.

   The map is rational because it works on an open part of its domain.

   They studied a rational map between two surfaces.

   Note
9. 9
   adjective

   Of a point on a shape in advanced math, having all its coordinates in the chosen number system.

   The point is rational because all its coordinates lie in the field.

   They searched for rational points on the curve.

   Note
10. 10
    adjective

    Of a chemical formula, showing how the parts of a compound are joined, not just which atoms it has.

    The teacher drew the rational formula to show how the atoms connect.

    A rational formula tells you more than just the number of atoms.

    Similargraphic

    Note
11. 11
    adjective

    Standing for a real, physical thing rather than just an idea.

    Here the symbol is rational because it points to a real object.

    A rational symbol represents an actual thing, not just an idea.

    Note
12. 12
    nounhistoricalcountable

    A jeweled chest piece worn by the high priests of ancient Israel.

    Like a fancy badge worn on the chest during an important ceremony.

    The high priest wore the rational over his robes during the ceremony.

    The Rationale of iudgement alſo thou shalt mke with embrodered worke of diuers colours, according to the workmanship of the Ephod of gold, hyacinth, and purple, and ſcarlet twiſe died, and twiſted ſilke.

    1609, The Holie Bible, Douay–Rheims BibleHere, Rationale means the jeweled breastplate worn by the high priest.

    Similarbreastplate, pectoral

    Note

Showing meanings only. Show all 12