class M planet n.
an Earth-type planet
Associated chiefly with the US TV series Star Trek.
You will confine your landings and contacts to Class ‘M’ planets, approximating Earth-Mars conditions.
Original outline for ‘Star Trek’ in S. E. Whitfield & G. Roddenberry Making of ‘Star Trek’ (1968) i. i. 24
Strategically it was the only Class M planet in the disputed zone.
Errand of Mercy in J. Blish Star Trek 2 (1968) 41
The planet he was referring to is a class M one.
Perry's Planet ii. 21
‘She’s class-M’, Lieutenant Lynch said of the red-orange world depicted on their main viewscreen.
My Brother’s Keeper ii. viii. 124
The next nearest habitable Class-M planet is two light-years away, in the middle of the Neutral Zone.
Dark Veil 71
any evidence 1964
Research HistorySuggested by Mike Christie on 9/15/02: "This is speculative since it may be just Star Trek, but googling '"class M planet" -trek' leads to quite a few hits."
Ben Ostrowsky submitted a 2021 cite from a Star Trek novel by James Swallow.
Last modified 2022-01-15 12:10:10
In the compilation of some entries, HDSF has drawn extensively on corresponding entries in OED.