a. 扣紧的

[ adj ]
furnished or closed with buttons or something buttonlike
<adj.all>

Button \But"ton\, v. t. [imp. & p. p. {Buttoned}; p. pr. & vb.
n. {Buttoning}.] [OE. botonen, OF. botoner, F. boutonner. See
{Button}, n.]
1. To fasten with a button or buttons; to inclose or make
secure with buttons; -- often followed by up.

He was a tall, fat, long-bodied man, buttoned up to
the throat in a tight green coat. --Dickens.

2. To dress or clothe. [Obs.] --Shak.

buttoned \buttoned\ adj.
furnished with buttons or something buttonlike. Opposite of
{unbuttoned}. [Narrower terms: {botonee, botonnee};
{button-down}; {closed}]
[WordNet 1.5]