in strangers in a strange land they talk about a terra year. what in the world is a terra year?

Second paragraph, “eight Terran years” ?

Yeah, regular Earth years. As the next bit talks about Smith growing up on Mars, which has a different length year, it’s just making the point that a year defined as “time taken for your planet to orbit the sun” depends which planet you are on.

a terra year is how long it takes the earth to go around the sun. That is to distinguish it for a Mars year which is a different length. When you are dealing with both Mars years and Earth years you have to say which you mean.

Terra means earth,so it means an earth year.

That would refer to a year’s time on earth.

Since other planets have years of differing lengths, an “earth year” of days distinguishes that from the years as measured on other planets.

a terra year would be by earth’s (terra) timetable.

so basically times that the sun rises and sets here, not by their sun (assuming there is one) rising and setting.

Earth’s time.