Datcha is a word originally arising from a corruption of the words "that's a". It is a contraction of "that's a" but can be used for other purposes. Other related words are ditcha ("this is a"), dotcha ("that was a"), and detcha ("this was a"). Also used in place of "that" or "that's" (rarely). All forms are interchangable with "an" or "a" (as in "Datcha airplane")
Person 1: Whoa, look! Datcha huge tree!
Person 2: Oh, wow, that is a huge tree!
Person 1: What are we supposed to do for 3 hours?
Person 2: Ditcha stupid (referring in this case not to "this is a stupid" but instead "this is stupid")
Person 1: What's that empty lot?
Person 2: Dotcha bookstore, but they tore it down.
Person 1: What are these layers of rock for?
Person 2: Detcha big old hill, but they blew it up.
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