arbitrary
日本語WordNet
based on or subject to individual discretion or preference or sometimes impulse or caprice; "an arbitrary decision"; "the arbitrary rule of a dictator"; "an arbitrary penalty"; "of arbitrary size and shape"; "an arbitrary choice"; "arbitrary division of the group into halves"
JMdict
AIによる解説
Based on random choice or personal whim, rather than any reason or system.
ライセンス: KeyLang Original
Here is what the anthropologist concluded after years of fieldwork: that cultural practices deemed arbitrary often serve adaptive functions, though their original purposes may become obscured over generations.
これは人類学者が何年ものフィールドワークの後に結論づけたことである:恣意的と見なされる文化的慣行はしばしば適応的機能を果たすが、その本来の目的は世代を超えて不明瞭になる可能性があるということ。
The arbitrariness of the decision frustrated many employees.
決定の恣意性は多くの従業員を苛立たせた。
Pronunciation data from ipa-dict (MIT License) based on cmudict-ipa by @lingz