填空题

Tsunami (海啸) is a Japanese word with the English translation, "harbor wave". Represented by two characters, the top character, "tsu" means harbor, while the bottom character, "nami" means "wave". In the past, tsunamis were sometimes referred to as "tidal-waves" by the general public, and were sometimes referred to as "seismic sea waves" by the scientific community. The term "tidal wave" is a misnomer; although a tsunami’s impact upon a coastline is dependent upon the tidal level at the time a tsunami strikes, tsunamis are unrelated to the tides. Tides result from the imbalanced, extraterrestrial, gravitational influences of the moon, sun, and planets. The term "seismic sea wave" is also misleading. "Seismic" implies an earthquake — related generation mechanism, but a tsunami can also be caused by a non-seismic event, such as a landslide or meteorite impact. From the passage we know that the word tsunami comes from (46) and it can be divided into two parts (47) .
Tsunami is not equal to words like (48) .
The underlined word "misnomer" means (49) .
The imbalanced, extraterrestrial, gravitational influences of the moon, sun, and planets resulted in (50) .