For *opvortet, from Proto-Indo-European *wortéyeti, causative stem (2nd conjugation) of the root of vertō (“to turn”) (3rd conjugation). Some refer the op- to ob-, some to opus, with which compare the similar expressions opus est and operam dare.
See also ligō, vinciō for other examples of words meaning to bind or turn, having derivatives with the sense of obliging.
oportet (present infinitive oportēre, perfect active oportuit); second conjugation, impersonal, no passive, no supine stem
| Conjugation of oportet (second conjugation, no supine stem, impersonal, active only) | |||||||
|---|---|---|---|---|---|---|---|
| indicative | singular | plural | |||||
| first | second | third | first | second | third | ||
| active | present | — | — | oportet | — | — | — |
| imperfect | — | — | oportēbat | — | — | — | |
| future | — | — | oportēbit | — | — | — | |
| perfect | — | — | oportuit | — | — | — | |
| pluperfect | — | — | oportuerat | — | — | — | |
| future perfect | — | — | oportuerit | — | — | — | |
| subjunctive | singular | plural | |||||
| first | second | third | first | second | third | ||
| active | present | — | — | oporteat | — | — | — |
| imperfect | — | — | oportēret | — | — | — | |
| perfect | — | — | oportuerit | — | — | — | |
| pluperfect | — | — | oportuisset | — | — | — | |
| imperative | singular | plural | |||||
| first | second | third | first | second | third | ||
| active | present | — | — | — | — | — | — |
| future | — | — | oportētō | — | — | — | |
| non-finite forms | active | passive | |||||
| present | perfect | future | present | perfect | future | ||
| infinitives | oportēre | oportuisse | — | — | — | — | |
| participles | oportēns | — | — | — | — | — | |
| verbal nouns | gerund | supine | |||||
| genitive | dative | accusative | ablative | accusative | ablative | ||
| oportendī | oportendō | oportendum | oportendō | — | — | ||