Hectar

According to the Writer's Guide, dated October 2, 1978, a hectar is defined as 9 million miles, or 1/10 of a parsec. The plural form is "hectare." The unit sectar may be a corruption of hectar.

See also: Units of Measure (TOS)

Original Series definition: a unit of distance, the Earth measurement being equivalent to 9 million miles (i.e. 1/10th of a parsec)