What is the meaning of Tret?

An allowance to purchasers, for waste or refuse matter, of four pounds on every 104 pounds of suttle weight, or weight after the tare is deducted.

Clipping of tretinoin.

simple past and past participle of treat, i.e. treated.

to dissolve, digest, melt down, lose weight

to throw away

trait

shot (with a gun)

except

past participle of treure

past participle of traure

Source: wiktionary.org