Here are some common abbreviations which come direct from the Latin:
ab init. ab initio: from the beginning
AD anno domini: in the year of the Lord
ad inf. ad infinitum: to infinity
ad int. ad interim: in the meantime
ad lib. ad libitum: at pleasure
a.m. ante meridiem: before noon
arg., Ag argentum: silver
Au aurum: gold
ca. , c. circa: about
Cantab. Cantabrigiensis: of Cambridge
Cantuar. Cantuariensis/Cantuarensis: of Canterbury
cf. confer: compare
con. contra: against
Cu cuprum: copper
cv curriculum vitae: course of life
DLitt Doctor Litterarum: Doctor of Letters
DPhil Doctor Philosophiae: Doctor of Philosophy
Dr doctor: teacher
DV Deo volente: God willing
e.g. exempli gratia: for example
ER Elisabeth Regina: Queen Elizabeth
et al. et alii: and the rest
etc. et cetera: and the rest, and so forth
et sequ. et sequens: and the following
ex div. extra dividendum: without dividend
ex lib. ex libris: from the books (of)
fec. fecit: made (it)
ib., ibid. ibidem: in the same place
id. idem: the same
i.e. id est: that is
imp. imprimatur: let it be printed
infra dig. infra dignitatem: beneath one’s dignity
inst. instant (from the Latin verb instare, to be present), the present month
lb libra: pound
loc. cit. loco citato: at the place cited
L.S.D. librae. solidi. denarii: pounds, shillings, pence
MCh Magister Chirugiae: Master of Surgery
MD Medicinae Doctor: Doctor of Medicine
Na natrium: sodium
nat. natus: born
nem. con. nemine contradicente: no one contradicting
non seq. non sequitur: it does not follow
ob. obiit: died
op. cit. opere citato: in the work cited
Oxon. Oxoniensis: of Oxford
Pb plumbum: lead
per cent per centum: in the hundred
per pro. per procurationem: for and on behalf of
PhD Philosophiae Doctor: Doctor of Philosophy
pinx. pinxit: painted
pro tem. pro tempore: for the time being
prox. proximo (mense): next (month)
PS post scriptum: written after (something)
QED quod erat demonstrandum: which was to be demonstrated
qv quod vide: which see
RIP requiescat in pace: may he/she rest in peace
sc. scilicet: namely
sd sine die: without a day (being fixed)
seq. sequens: following
ult. ultimo: in the last (month)
ut dict. ut dictum: as said
v versus: against
verb. sap. verbum sapienti: a word to the wise (is enough)
vid. vide: see
viz. videlicet: namely