What it means
いわゆる means “the so-called” and is used before a noun to present a commonly recognized label or category. It can simply identify something by its conventional name, but it may also suggest that the speaker is questioning, qualifying, or keeping some distance from that label. It is an attributive expression and normally cannot be used by itself as the predicate of a sentence.
Usage note
いわゆる does not always express criticism or doubt; the exact nuance depends on context. It directly modifies the noun that follows it, as in いわゆる専門家, rather than functioning like an ordinary predicate.
How to use it
いわゆる成功者は、努力を惜しみません。
The so-called successful person does not spare effort.
いわゆる成功者は、努力を惜しまない。
The so-called successful person does not spare effort.
Example sentences
市役所は、いわゆる地域猫の活動を支援するため、避妊手術の費用を一部助成している。
The city government partially subsidizes the cost of sterilization surgery to support activities involving so-called community cats.
この本は、いわゆる入門書として大学の授業でも使われている。
This book is also used in university classes as what is commonly called an introductory book.
週末には、いわゆるデジタルデトックスのために、スマートフォンの電源