Manure

From Memory Alpha, the free Star Trek reference

Manure is the name applied to the waste products of lifeforms primarily used in agriculture. This can include horses and cows.

One component of manure is methane. Kathryn Janeway recognized this upon detecting methane on a truck found in 2372. (VOY: "The 37's")

Some will use the term manure as a metaphor for purposes of making a derogatory comment. The Species 8472 recreation of Boothby once referred to the Federation's concepts of "tolerance for all species" and the Prime Directive as Targ manure. (VOY: "In the Flesh")