What does irrational mean?
Word: Irrational
Part of Speech: Adjective
Meaning: Irrational means not based on clear thinking or good sense.
Synonyms: unreasonable
How do you spell irrational?
Syllables: ir - ra - tion - al
Tricky part: The sh sound in the middle is not written with sh, so pupils try irrashonal or irrasional.
Watch out for: irrashonal, irrasional
Memory tip: Think of the sh sound here as a t in disguise, wearing a sound that is not its own.
Irrational in a sentence
Example 1: Refusing to taste a new dish before even seeing it is a little irrational.
Example 2: Buying a bigger bag just because it is on sale can be an irrational choice.
Example 3: Shouting at a slow computer is irrational, since it cannot hear you.
Fun Fact
The word belongs to a large family. Ratio and reason both come from the same Latin word as this one, a word that meant reckoning or working something out.
Practise the CREST Way
Word Makeup
Choose the prefix that completes the word:
rational
a) un
b) in
c) ir
d) im
Show answer
c) ir. Before a word starting with r, this form of the not-prefix is used, as in irregular and irresponsible.
Word Cookie
Find the extra letter in the word:
irrationall
a) n
b) l
c) r
d) t
Show answer
b) l. Adjectives ending this way, like national, stop after one of this letter.
Word Connection
Choose the antonym of the word:
irrational
a) logical
b) absurd
c) senseless
d) baseless
Show answer
a) logical. A logical plan follows sound reasoning step by step.
Mingle-Mangle
Form a meaningful word from the jumbled letters:
tolarriani
a) invitation
b) irritation
c) irrational
d) irrigation
Show answer
c) irrational. Irritation and irrigation have too many i's and no l, and invitation has a v.
Multiple Choice Questions
1. Spot the irrational belief.
a) A good sleep keeps me alert in class.
b) Revising helps me do well in tests.
c) Daily practice improves my bowling.
d) Skipping every lesson will improve my marks.
Show answer
d) Skipping every lesson will improve my marks.
2. Someone in an irrational mood will tend to ____.
a) weigh up both sides before deciding
b) check the facts with a good book
c) refuse sensible advice for no reason
d) ask a teacher to explain the rule
Show answer
c) refuse sensible advice for no reason
