The subject of a branch of knowledge; the subject matter of a study. Obsolete.

Field of inquiry; field of discussion or debate, subject of debate. Obsolete.

A ‘field’ of inquiry, study, etc.

figurative. A sphere of thought or action; field, province, scope of a department of knowledge, etc.

figurative. ‘Field’ (of view, observation, research, etc.); expanse.

figurative. With allusion to a metaphorical ‘travelling’ or the like: subject matter, things that may be the object of study or discourse. Also rarely…

one's line of country, one's pursuit, field of interest, area of study, etc. (Frequently in neg. contexts.) Also, line of work.