Friar
Webster's Dictionary [1]
(1): ( n.) A brother or member of any religious order, but especially of one of the four mendicant orders, viz: (a) Minors, Gray Friars, or Franciscans. (b) Augustines. (c) Dominicans or Black Friars. (d) White Friars or Carmelites. See these names in the Vocabulary.
(2): ( n.) An American fish; the silversides.
(3): ( n.) A white or pale patch on a printed page.
Charles Buck Theological Dictionary [2]
(brother, ) A term common to the monks of all orders. In a more peculiar sense, it is restrained to such monks as are not priests: for those in orders are usually dignified with the appellation of father.
Cyclopedia of Biblical, Theological and Ecclesiastical Literature [3]
(Lat. frater, Fr. frere, brother), a term common to monks of all kinds, founded on the supposition that there is a brotherhood between the persons of the same monastery. It is especially applied to members of the four mendicant orders, viz.
1. Franciscans, Minorites, or Gray Friars;
2. Augustines;
3. Dominicans, or Black Friars;
4. Carmelites, or White Friars.
In a more restricted sense, the word means a monk who is not a priest: those in orders are generally denominated father.
The Nuttall Encyclopedia [4]
E . brother), a name applied generally to members of religious brotherhoods, but which in its strict significance indicated an order lower than that of priest, the latter being called "father," while they differed from monks in that they travelled about, whereas the monk remained secluded in his monastery; in the 13th century arose the Grey Friars or Franciscans, the Black Friars or Dominicans, the White Friars or Carmelites, Augustinians or Austin Friars, and later the Crutched Friars or Trinitarians.