The phrase "almost duplicate" is correct and usable in written English.
It can be used to describe something that closely resembles or is very similar to another item, but is not an exact copy.
Example: "The two reports are almost duplicates, with only minor differences in the data presented."
Alternatives: "nearly identical" or "close copy".
Two boards on the final day were almost duplicates.
The currents of the North Pacific move in a clockwise spiral that almost duplicates the pattern in the North Atlantic.
The title story, a fantastic riff upon a fantasy, almost duplicates Fitzgerald's for a few sentences but goes off weirdly in its own directions.
In the same year, the icebreaker Georgy Sedov (originally the Newfoundland sealing steamer Beothic), under the command of Konstantin Sergeyevich Badigin, was caught in the ice in the Laptev Sea and began a 27-month drift across the Arctic basin that almost duplicated that of the Fram and yielded useful comparative data.
Type of Ge distribution in the depth profile of the wetting layer almost duplicates the buffer layer geometry (Fig. 4b).
Almost duplicating the recorded version, this live version has an element of Pink Floyd that I always loved but rarely heard on recordings... Roger Waters' punk-bass playing!
The photo does an incredible job of capturing this tension, a tension almost duplicated in the highway scene between Tony's family and Ray's gang.
"And I think that's something that's important going into the playoffs because that's the objective — to win that game, and I think we have finally figured out that every game is an individual game and I think they do a good job of doing that". The Clippers, who overcame a 17-point deficit to win at Phoenix on Wednesday, almost duplicated that against Dallas but couldn't hold on.
The distance from the centre of the nucleus of each cell to the peripheral fringe of the Golgi was almost duplicated in infected cells, in the presence as well as in the absence of AraC, when compared to non-infected cells, and was highly significant according to T test (P < 0.0001).
