When you watch an anime, usually there are Romanized words which are not translated into English. From those words, we can know what the meaning of certain words through hearing, even without knowing their Japanese spelling. The Romanized Japanese terms used actually are the general terms in daily life.
This term is usually used when a character wants to ridicule another as a fool. The meaning itself is fool idiot, or stupid.
Kawai is referred as cute.
Sake is kind of alcoholic drinks made from the brewed rice.
Dojikko is the term when the character is depicted as a clumsy-cute girl, who often hurt herself.
Tsundere is a character that looks cold, rude, and heartless, but actually, that person is warm-hearted and lovable.
Yandere is the reverse of tsundere. The character looks lovely, warm, and nice in the front but he or she is hiding the psychotic or brutal traits within themselves.
Bishoujo is the term that depicts the young and attractive women. But sometimes is also referred as a sexually attractive woman.
Bishounen is generally for the term of the young beautiful boy. So, it is the term to depict someone androgynously or look like a girl faced.