for the most part; " he is mainly interested in butterflies"

In the first place; principally; preeminently; above; especially.

In the first place: principally: for the most part.

Principally; for the most part.

Principally; especially; above all.

Especially; mainly; principally; in the first place.

It will be unpleasant to us all, but I am thinking chiefly of you. – The Eustace Diamonds by Anthony Trollope

This he said looking chiefly at Mr. Somers, and then turning to his cousin, he asked him if he intended to remain in the country. – Castle Richmond by Anthony Trollope

A definition like that which is given above, may answer in some degree the purpose of distinction; but, after all, we must judge what is, and what is not a verb, chiefly from our own observation of the sense and use of words. – The Grammar of English Grammars by Goold Brown

Relative mental mass and relative mental complexity have chiefly to be observed. – Essays: Scientific, Political, & Speculative, Vol. I by Herbert Spencer

The history of the town is chiefly a record of " Old unhappy far- off things, And battles long ago." – In the Border Country by W. S. (William Shillinglaw) Crockett

Indeed, if you must shoot anybody, it should be chiefly yourself, and after that your father, and mother, and sisters. – Orley Farm by Anthony Trollope

He asked her if she could venture to look back on her dream so as to mention what had chiefly distressed her. – The Clever Woman of the Family by Charlotte M. Yonge

The Duc died last year, chiefly of grief for the death of another daughter who had married a Frenchman. – Story of My Life, volumes 1-3 by Augustus J. C. Hare

These objects are chiefly telescopic, and are thus in strong contrast to the splendid comet of Halley. – The Story of the Heavens by Robert Stawell Ball

Her own life romance was a buried chapter, and now she was chiefly concerned for the happiness of the two young persons seated there. – Idle Hour Stories by Eugenia Dunlap Potts

I expect it's chiefly a matter of careful hunting." – The Manor House School by Angela Brazil

Its superior extremity is chiefly represented by the olecranon process, which is voluminous in bulk, and forms the projection known as the point of the elbow. – Artistic Anatomy of Animals by Édouard Cuyer

We shall go to the point I chiefly came here to settle. – East Lynne by Mrs. Henry Wood

For myself, I pass my time chiefly at Cnidos: you must come and visit me there. – Ixion In Heaven by Benjamin Disraeli

He was chiefly remarkable for his perfect self- possession. – The Price She Paid by David Graham Phillips

They were chiefly selling country produce. – Mopsa the Fairy by Jean Ingelow

From which Leslie understood that the person whom she chiefly had come to see was out. – Aurora the Magnificent by Gertrude Hall

But he writes to me on social matters chiefly. – Marcella by Mrs. Humphry Ward

If they discover you are one with them, and that in your efforts to keep order you have the welfare of the school chiefly at heart, they will come out, depend upon it, and meet you half- way. – The Willoughby Captains by Talbot Baines Reed

The afternoon was advancing, and, as a matter of fact, the fight lasted in all only a couple of hours altogether- chiefly a matter of artillery. – In the Yellow Sea by Henry Frith