Dictionary entry

Chiefly

Webster's Dictionary 1913

Chief″ly (?), adv. 1. In the first place; principally; preëminently; above; especially.

Search through this garden; leave unsearched no nook;

But chiefly where those two fair creatures lodge.

Milton.

2. For the most part; mostly.

Those parts of the kingdom where the... estates of the dissenters chiefly lay.

Swift.