Difference in usage of gairaigo and wago?

[Hemem]

Please help me to understand how and when english-derived words are used in modern Japanese?
I understand that ko-hi and garasu didn't exist in Japan, so there are no Japanese words for them. But I found that there exist gairaigo for such words as "knife" and "husband" and many others, which obviously exited as phenomenons BEFORE .
So, could you please explain and give examples from your experience? Which words are preferable where?
Are they all interchangeable, can they be used in scientific speech/text, in formal speech/text?

バカンス/休暇
ビル/建物
チケット/切符
ファイナル/最後
ママ/おかあさん
ミルク/牛乳
バッグ/鞄
ゼロ/零
アルバイト/働き
サラリーマン/社員
ドイツ/独国

[community.japanese]

Hi!
Thanks for the question.

バカンス/休暇 >> People also use バケーション (derived from English). In business documents, 休暇 is preferred but in casual conversation or social media, young people mostly use バカンス and バケーション.

ビル/建物 >> In business and legal document, 建物 is used. If you ask a direction, most people use ビル, like 「あの茶色いビルの角を右に曲がって...」etc.

チケット/切符 >> 切符 is mostly used when taking about trains, subways and buses. チケット is commonly used for concert, sports, etc. in order to enter a venue.

ファイナル/最後 >> Need to know more context but people use 最後 more frequently. If you are talking about "final exams" people use 「期末（きまつ）テスト」, not ファイナルテスト.

ママ/おかあさん >> Most toddlers in Japan use ママ. When kids become older, around elementary school age, they use おかあさん mostly as the term ママ is associated with childhood and people make fun of you if you keep using it when you get older.

ミルク/牛乳 >> 牛乳 is commonly used. ミルク is used to describe baby formula or like in ミルクティー (Black tea with milk).

バッグ/鞄 >> バッグ is commonly used. Some old people prefer to use 鞄.

ゼロ/零 >> These are interchangeably used. In newscast, they use 零 (I think there's a rule on how to pronounce "number 0.")

アルバイト/働き >> アルバイト is widely used.

サラリーマン/社員 >> サラリーマン is widely used. 会社員 is more commonly used than 社員 to describe people in workforce.

ドイツ/独国 >> ドイツ is used.

Sincerely,
Miki H
Team JapanesePod101.com