modus n.

Proto-Indo-European root meaning "take appropriate measures."

It forms all or part of: accommodate; accommodation; commode; commodious; commodity; empty; immoderate; immodest; Medea; medical; medicament; medicaster; medicate; medication; medicine; medico; medico-; meditate; meditation; Medusa; meet (adj.) "proper, fitting;" mete (v.) "to allot;" modal; mode; model; moderate; modern; modest; modicum; modify; modular; modulate; module; modulation; mold (n.1) "hollow shape;" mood (n.2) "grammatical form indicating the function of a verb;" must (v.); premeditate; premeditation; remedial; remediation; remedy.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit midiur "I judge, estimate;" Avestan vi-mad- "physician;" Greek mēdomai "be mindful of," medesthai "think about," medein "to rule," medon "ruler;" Latin meditari "think or reflect on, consider," modus "measure, manner," modestus "moderate," modernus "modern," mederi "to heal, give medical attention to, cure;" Irish miduir "judge;" Welsh meddwl "mind, thinking;" Gothic miton, Old English metan "to measure out."

"way of doing or accomplishing," 1650s, Latin, literally "mode of operating" (see modus). Abbreviation m.o. is attested from 1955.

"mode of living," especially a working agreement between contending parties, 1844, Latin, literally "way of living or getting along" (see modus).

Modus vivendi is any temporary compromise that enables parties to carry on pending settlement of a dispute that would otherwise paralyse their activities. [Fowler]