dashi だし

In Japanese, dashi だし is the da だ copula plus the shi し particle. The shi し particle is used to list facts, reasons, and so on, and it comes after the predicative form of words.

For some words, the predicative form ends in the da だ copula, that's when it forms dashi だし, but for other words, like i-adjectives, it does not, and you end up with just shi し.

Beware of homonyms: dashi 出し, "putting out," the noun form of dasu 出す, "to put out," can also mean a Japanese kind of soup stock.

Manga: Komi-san wa, Comyushou desu. 古見さんは、コミュ症です。 (Chapter 14, あがり症です)

• Context: regarding Komi-san 古見さん.
• bijin dashi,
  atama mo ii shi,
  ninkimono dashi,
  美人だし、頭もいいし、人気者だし、
  [She] is a beautiful-person, [she] is also smart, [she] is a popular-person,
  • atama ga ii 頭がいい
    Literally "head is good."
    To be smart.
  • Here, shi し comes after words in their predicative forms.
  • For adjectives like bijin and ninkimono, those forms are bijin da and ninkimono da, with the predicative copula da だ.
  • For an i-adjective like ii いい, "good," the da だ copula isn't necessary, so shi し comes right after it.