Hi,

In Zoega we have:
brók (-ar, pl. brœkr), f. (1) one leg of a pair of breeches (ok lét hann leika laust knéit í brókinni); (2) breeches (but the pl.'brœkr' is more common); vera í brókum, to wear breeches; gyrðr í brœkr, with breeches girt over one's underclothing.

Re ok lét hann leika laust knéit í brókinni, does it mean something like HE LET HIS KNEE PLAY LOOSE (I.E. DANGLE) IN HIS TROUSER LEG?

Best wishes,

Simon