Latin in English.
from: Tom McArthur, The Oxford Companion to the English Language (1992)
A large part of the lexicon of Latin has entered English in two major waves: mainly religious vocabulary from the time of Old English until the Reformation, and mainly scientific, scholarly, and legal vocabulary (slightly different in English and Scottish law), from the Middle Ages onwards. In the 17C, such makers of English dictionaries as John Bullokar deliberately converted Latin words into English building on the already strong French component of the vocabulary so as to create a Latinate register of education and refinement. In it words like fraternity and feline were set lexically and stylistically 'above' words like brotherhood and cat. These lexicographers' methods were straightforward: they turned the endings of Latin words into Anglo-French endings, a practice that has continued with minor modifications ever since: thus, alacritas became French-like alacritie (later alacrity), catalogus (Greek in origin) became catalogue (later catalog in AmE), incantatio became incantation, onerosus became onerous, puerilis became puerile, and ruminare (through its past participle ruminatus) became ruminate.
Such processes are so transparent to those with a knowledge of Latin morphology that they can usually without much difficulty identify relationships between basic Latin forms and words derived from them in languages like Spanish, French, and English. The majority of such forms are either verbal or nominal-adjectival, the verbal relating to the four Latin conjugations the nominal-adjectival relating mainly to three of the five Latin declensions. Latin verb routinely listed with two canonical forms the infinitive and the neuter of the past participle: amare/amatum to love (first conjugation); monere/monitum to warn (second); regere/rectum to rule (third); audire/auditum ) to I hear (fourth). Latin nouns and adjectives are often often listed using two categories of case (nominative for the subject of a sentence, genitive for possession): regina/reginae queen, nigra nigrae black (both first declension); dominus /domini master, ager/agri field, magnus/magni great in niger/nigri black (all second); rex/regis king i nobilis/nobiliis noble (both third).
The bulk of words in Latin-derived English relate etymologically and structurally to these two broad types. For example, from the verb cantare/cantatum (to sing, usually with form -cent- after a prefix) come such word as cant, canticle, cantor, descant, incantation, accent, incentive, preceptor, recant (with enchant, enchantment through French, and cantata, canto through Italian). From monere/monitum to warn) come monitor, admonish, admonition, admonitory, premonition. From agere / actum do, act) come agent, agency, agile. agility, agitate, act, actor, action, enact, exact, inaction, inactivity. From currere/cursum (to run) come current, currency, cursive, cursor, cursory, concur, incur, excursion, occurrence, precursor, recurrent. From claudere/clausum (to close, with the forms -clud-/-clus- after a prefix) come clause, include, exclude, preclude, seclusive, conclusion. From dominus/domini (master) and dominare / dominatum (to master) come dominion, dominate, domination, dominie, domineering (through French and Dutch), domain (through French). From caput/capitis (head) come capital, capitalism, capitalize, decapitate, decapitation (and through French cattle, chapter, chattel/ chief). From avidus/avidi (greedy) come avid. avidity; from rigidus/rigidi (stiff) come rigid, rigidity; from audax/audacis (bold) come audacious, audacity; from ferox/ferocis (fierce) come ferocious, ferocity.
In addition, many words that in Latin actually perform grammatical functions have been nominalized in English: caveat (beware) as a synonym for a warning, floruit (he/she flourished) to mark the period when someone was in his her prime (usually when precise birth and death dates are not known), imprimatur (let it be printed) for someone's approval of a published text, quorum (of whom) the minimum number people necessary for a committee or similar meeting, tandem (at length) for a bicycle built for two. Similarly, many phrases and sentences of Latin are perpetuated as tags and mottoes: ad astra per aspera to the stars through hardship (the motto of the US state of Kansas), per ardua ad astra through difficulties to the stars (the motto of the Royal Air Force), habeas corpus you may have the body (a technical term in law) ....