名詞 irrational:

1. a real number that cannot be expressed as a rational number
   同義詞：irrational number

形容詞 irrational:

1. not consistent with or using reason
2. real but not expressible as the quotient of two integers

1. The state or quality of being irrational.
   不理智不理智的狀態(tài)或性質(zhì)
2. She traced her irrational fear of birds back to something which had happened to her as a child.
   她從她童年的經(jīng)歷中找到了她對(duì)鳥類莫名恐懼感的原由。
3. She was prey to irrational fears.
   她遭受著無端恐懼的折磨。
4. An irrational idea, expression, or act.
   不合理的事物非理性的想法，表達(dá)法，或行為

ir.ra.tion.al

adj.（形容詞）

Not endowed with reason.
不具有理智的
Affected by loss of usual or normal mental clarity; incoherent, as from shock.
失去理性的：因喪失通常或正常的清醒頭腦而受影響的；不連貫的，如受驚嚇后所表現(xiàn)的那樣
Marked by a lack of accord with reason or sound judgment:
不理智的：不聽從理性的或缺乏正確判斷的：
例句：
an irrational dislike.See Synonyms at meaningless See Synonyms at unreasonable
不理智的憎惡參見 meaningless參見 unreasonable

Being a syllable in Greek and Latin prosody whose length does not fit the metric pattern.
希臘和拉丁詩(shī)歌韻律學(xué)中中長(zhǎng)度不符合格律的音節(jié)的
Being a metric foot containing such a syllable.
音步含有這樣一個(gè)音節(jié)的
Mathematics Of or relating to an irrational number.
【數(shù)學(xué)】 無理數(shù)的：無理數(shù)的或與無理數(shù)有關(guān)的

【引伸】
irra.tionally
adv.（副詞）
irra.tionalness
n.（名詞）