plural -s
: the process of collimating an instrument (such as a telescope) having objective and cross hairs by directing it toward a plane mirror and adjusting the lens and cross hairs so that the latter coincide with their own reflected image

Word History


aut- + collimation

First Known Use

1870, in the meaning defined above

Time Traveler
The first known use of autocollimation was in 1870

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Dictionary Entries Near autocollimation

Cite this Entry

“Autocollimation.” Dictionary, Merriam-Webster, Accessed 28 Sep. 2023.

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