Is there a (Japanese) linguistic term for okurigana omission (cases when 問い合わせ is written as 問合せ, etc.)? If not then what would be a concise way to refer to the phenomena (in Japanese)?
2 Answers
Being a non-linguist, I have no idea if this term is used in linguistics, but our 文化庁{ぶんかちょう} (Agency for Cultural Affairs) calls it 「許容{きょよう}」 ("tolerance").
http://www.bunka.go.jp/kokugo_nihongo/sisaku/joho/joho/kakuki/10/tosin01/02.html
To refer to the phenomenon, you could use a phrase like:
「誤読{ごどく}の可能性{かのうせい}が低{ひく}い(単{たん})語{ご}の送{おく}り仮名{がな}の省略{しょうりゃく}」
That would be understood by all native-speakers, I promise.
The word 送る seen in okurigana (送り仮名) is the term to mean "put okurigana".
For example you could say:
「問い合わせ」の「せ」だけ送る (you'll get 問合せ)
「申し込み」の「し」は送らない (you'll get 申込み)
「終わる」は「わる」と送る (you'll get 終わる instead of 終る)