per annum, diem or mensem /anˈəm or -ŭm, dīˈəm or dēˈem, or menˈsəm or menˈsem/

Yearly, daily or monthly

per ardua ad astra /ärˈdū-ə ad asˈtrə or ärˈdŭ-ä ad asˈträ/

By steep and toilsome ways to the stars (the motto of the RAF)

per capita /kapˈi-tə or kapˈi-tä/ or per caput /kapˈŭt/

1. (counting) by heads
2. For each person
3. All sharing alike

per contra /konˈtrə or konˈträ/

1. On the contrary
2. As a contrast

per curiam /kūˈri-am or kooˈri-am/ (law)

By a court

per fas et nefas /fas et nēˈfas or fäs et neˈfäs/

Through right and wrong

per impossibile /im-po-siˈbi-lē or im-po-siˈbi-le/

1. By an impossibility
2. If it were so, which it is not

per incuriam /in-kūˈri-am or in-kooˈri-am/ (law)

Through lack of care, a phrase designating a court decision that is given in ignorance of the relevant statute, and therefore not binding as a precedent

per minas /mīˈ or mēˈnäs/ (law)

By means of threats, by menaces

per procurationem /prok-ū-rā-shi-ōˈnem or prō-koo-rä-ti-ōˈnem/

By the agency of another, by proxy

per saltum /salˈtəm or salˈtŭm/

1. At a single leap
2. All at once

per se /sē or sā/

1. By himself, etc
2. Essentially
3. In itself

per stirpes /stûrˈpēz or stirˈpās/

(of an inheritance) bequeathed in blocks to families who subdivide it equally among the members, rather than directly to individuals themselves (per capita)