Webster's Revised Unabridged Dictionary · 1913

Busy

Busy (biz"zy) , adjective

[Old English busi, bisi, Anglo-Saxon bysig; akin to Dutch bezig, LG. besig; compare Sanskrit bhūsh to be active, busy.]

1.
Engaged in some business; hard at work (either habitually or only for the time being); occupied with serious affairs; not idle nor at leisure; as, a busy merchant.
Sir, my mistress sends you word That she is busy, and she can not come. — Shakespeare
2.
Constantly at work; diligent; active.
Busy hammers closing rivets up. — Shakespeare
Religious motives... are so busy in the heart. — Addison
3.
Crowded with business or activities; -- said of places and times; as, a busy street.
To-morrow is a busy day. — Shakespeare
4.
Officious; meddling; foolish active.
On meddling monkey, or on busy ape. — Shakespeare
5.
Careful; anxious. [Obsolete] — Chaucer

Busy (biz"zy) , transitive verb

[Anglo-Saxon bysgian.]

To make or keep busy; to employ; to engage or keep engaged; to occupy; as, to busy one's self with books.
Be it thy course to busy giddy minds With foreign quarrels. — Shakespeare