Denshi Jisho — Online Japanese dictionary

書留 かきとめ 1: (Abbreviation) registered mail;
2: registration (e.g. of mail); writing down; putting on record; recording; making a note of
Common word, Noun, Suru verb, No-adjective 
書留め かきとめ 1: (Abbreviation) registered mail;
2: registration (e.g. of mail); writing down; putting on record; recording; making a note of
Irregular okurigana usage, Noun, Suru verb, No-adjective 
書留料 かきとめりょう registration fee
Noun 
書留小包 かきとめこづつみ registered parcel
Noun 
書留郵便 かきとめゆうびん registered mail; PD PR
Noun 

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