full of shit, Usedtodescribesomeonewhoislyingornottellingthetruth.
scared shitless, Extremelyfrightenedorterrified.
Word Origin
Language
Old English
Original word
scitte
Originally meant
to separate, to defecate
Background
The word 'shit' originates from the Old English 'scitte', which referred to diarrhea. It has been used as a vulgar term for feces since at least the 14th century.