c. 1300, "to transfer, convey, bequeath (property); appoint (to someone a task to be done); order, direct (someone to do something); fix, settle, determine; appoint or set (a time); indicate, point out," from Old French assigner "assign, set (a date, etc.); appoint legally; allot" (13c.), from Latin assignare/adsignare "to mark out, to allot by sign, assign, award," from ad "to" (see ad-) + signare "make a sign," from signum "identifying mark, sign" (see sign (n.)). Its original use was in legal transfers of personal property. Related: Assigned; assigning.
"to soften," usually figuratively, of pain, anger, passion, grief, etc., c. 1300, from Anglo-French assuager, Old French assoagier "soften, moderate, alleviate, calm, soothe, pacify," from Vulgar Latin *adsuaviare, from Latin ad "to" (see ad-) + suavis "sweet, agreeable" (from PIE root *swād- "sweet, pleasant;" see sweet (adj.)). For sound development in French, compare deluge from Latin diluvium, abridge from abbreviare. Related: Assuaged; assuaging.
1704, "a collection of individuals," from French assemblage "gathering, assemblage," from assembler (see assemble). Earlier English words in the same sense include assemblement, assemblance (both late 15c.). The meaning "act of coming together" is from 1730; that of "act of fitting parts together" is from 1727.
c. 1600, "declare;" 1640s, "vindicate, maintain, or defend by words or measures," from Latin assertus, past participle of asserere/adserere "to claim, lay claim to, appropriate," from ad "to" (see ad-) + serere "to join together, put in a row" (from PIE root *ser- (2) "to line up"). Related: Asserted; asserting. To assert oneself "stand up for one's rights or authority" is recorded from 1879.
"diligence," early 15c., from Latin assiduitatem (nominative assiduitas) "continual presence," noun of quality from assiduus "continually present" (see assiduous).
Industry keeps at work, leaving no time idle. Assiduity (literally, a sitting down to work) sticks quietly to a particular task, with the determination to succeed in spite of its difficulty, or to get it done in spite of its length. Application, literally, bends itself to its work, and is, more specifically than assiduity, a steady concentration of one's powers of body and mind .... [Century Dictionary]
early 14c., assignacioun, "appointment by authority," from Old French assignacion (14c., Modern French assignation), from Latin assignationem (nominative assignatio) "an assigning, allotment," noun of action from past-participle stem of assignare/adsignare "to mark out, to allot by sign, assign, award," from ad "to" (see ad-) + signare "make a sign," from signum "identifying mark, sign" (see sign (n.)).
The meaning "action of legally transferring" (a right or property) is from 1570s; that of "a meeting by arrangement, tryst" is from 1650s, especially for a love-affair; assignation-house (1849) was an old euphemism for "brothel."
mid-15c., assistent "one who helps or aids another," from Latin assistentem (nominative assistens), noun use of present participle of assistere "stand by, attend" (see assist (v.)). The spelling changed in French then (16c.) in English.