Systematic \Sys`tem*at"ic\, Systematical \Sys`tem*at"ic*al\, a. [Gr. ?: cf. F. syst['e]matique.]

1. Of or pertaining to system; consisting in system; methodical; formed with regular connection and adaptation or subordination of parts to each other, and to the design of the whole; as, a systematic arrangement of plants or animals; a systematic course of study.

Now we deal much in essays, and unreasonably despise systematical learning; whereas our fathers had a just value for regularity and systems. --I. Watts.

A representation of phenomena, in order to answer the purposes of science, must be systematic. --Whewell.

2. Proceeding according to system, or regular method; as, a systematic writer; systematic benevolence.

3. Pertaining to the system of the world; cosmical.

These ends may be called cosmical, or systematical. --Boyle.

4. (Med.) Affecting successively the different parts of the system or set of nervous fibres; as, systematic degeneration.

Source: Webster's Revised Unabridged Dictionary (1913)