Could meeder be madder? I've seen some spellings for madder that are way off, mayder, maider. Kinda wide guess, but since it's cloth that it's referring to, then it could possibly be the colour.

vide? Hmmm. Latin origin for 'see'. All I got. ;)

btw, first thing I thought of when I saw truss, was suspenders or corsets (men wore shaping garments too).