お大事に[odaijini] take care of yourself
暗黒大陸[ankokutairiku] Dark Continent (i.e. Africa)
伊勢大神宮[isedaijinguu] the Grand Shrines of Ise
伊勢大廟[isetaibyou] the Grand Shrines of Ise
偉大[idai] greatness

医科大学[ikadaigaku] medical school
医大[idai] medical university
井の中の蛙大海を知らず[inonakanokawazutaikaiwoshirazu] parochial
一大[ichidai] one large ...
一大事[ichidaiji] serious affair

サンプリング周波数[sanpuringushuuhasuu] sampling frequency
波蘭[poorando] Poland
マイクロ波[maikuroha] microwave
ミリ波[miriha] milli-wave
圧力波[atsuryokuha] pressure wave

伊呂波[iroha] traditional ordering of the Japanese syllabary
浦波[uranami] (seaside) breakers
横波[yokonami] side (transverse) wave
音波[onpa] sound wave
寒波[kanpa] cold wave