"absent in mind, distracted from present reality by intellectual activity," 1640s, past-participle adjective from abstract (v.). Related: Abstractedly.

An absent man is one whose mind wanders unconsciously from his immediate surroundings, or from the topic which demands his attention; he may be thinking of little or nothing. An abstracted man is kept from what is present by thoughts and feelings so weighty or interesting that they engross his attention. [Century Dictionary]

[area], mid-15c., "extent, continued passage or duration," in phrase tract of time "period or lapse of time" (now obsolete), from Latin tractus "course, progress, movement, a train or course, a space drawn out, duration," etymologically "a drawing out or pulling," from stem of trahere "to pull, draw." This is said [Watkins] to be from a PIE root *tragh- "to draw, drag, move" (source also of Slovenian trag "trace, track," Middle Irish tragud "ebb;" perhaps with a variant form *dhragh-; see drag (v.)). Compare trait and trace (n.1).

The meaning "territory, region of indefinite extent, stretch of land or water" in English is recorded by 1550s. Latin tractus also had a sense of "territory, district, region of land." The specific U.S. sense of "plot of land for development" is recorded from 1912; tract housing is attested by 1953.

Also by 1680s in anatomy, in reference to regions of the body having particular functions (digestive, respiratory, etc.).

late 14c., "by itself, absolutely, unconnected with anything else," from abstract (adj.) + -ly (2).

"to subtract" in any sense, 1540s, "Now illiterate" [OED], "An erroneous form of subtract, common in vulgar use" [Century Dictionary], from Modern Latin substractus, past participle of substrahere, an alternative form of subtrahere "take away" (see subtraction). The form probably is suggested by abstract (v.) from Latin abstrahere. Related: Subtracted; subtracting; substrahend.

word-forming element meaning "away, from, from off, down," denoting disjunction, separation, departure; from Latin ab (prep.) "off, away from" in reference to space or distance, also of time, from PIE root *apo- "off, away" (also the source of Greek apo "off, away from, from," Sanskrit apa "away from," Gothic af, English of, off; see apo-).

The Latin word also denoted "agency by; source, origin; relation to, in consequence of." Since classical times usually reduced to a- before -m-, -p-, or -v-; typically abs- before -c-, -q-, or -t-.