Search gender: all male female Masadai Boy Name Meaning, Kanji Variations. 1 names found. gender: all male female Name: masadai Katakana: マサダイ 0 Kanji: 昌大 Meaning: 昌Thriving. vigorous. Explicit. bright. good. beautiful. Splendid. Sunlight. 大Big. Large. Large in number or quantity. Greatly. Valuable. Important. Excellent. Splendid. Very much. Much. (Power or force) strong. long time. To be high in rank or position. You can save your favorite names with NAZUKE PON > About Japanese Names > Search For Japanese Names > Masadai Boy Name Meaning, Kanji Variations.