Green’s Dictionary of Slang

crap, the phr.

1. [1930s+] (orig. US) the essence, the stuffing; esp. in phrs. below.

2. [1940s+] (orig. US) a euph. for hell, the phr. (1) used in questions, e.g. what the crap do you want?

In phrases

kick the crap out of (v.)

[1930s+] (orig. US) to beat up.

knock the crap out of (v.) (also beat the crap out of, slap the crap out of)

1. [1940s+] (orig. US) to beat up.

2. [2000s] in fig. sense, to malign.

scare the (living) crap out of (v.)

[1960s+] to terrify.