Lewis & Short

fartim, adv. [farcio], by stuffing or cramming; hence, closely, densely (post-class.): tectum omne fartim stipaverant, App. M. 3, p. 130, 12: isicium fartim concisum, i. e. cut up fine as if for stuffing, id. ib. 2, p. 117, 30.