-idus

Forms

-idus (feminine -ida, neuter -idum); first/second-declension suffix^[1]

Etymology

The suffix is inherited from Proto-Italic *-iðos, from Proto-Indo-European *-dʰh₁-os, a thematized formation from *dʰeh₁- (“to put, place”), originally attached to i-stems.^[1] Weiss likewise derives it from *-idho-, with the further analysis into /*-i-/ and the root of “put”, which he credits to Hackstein, Balles and earlier Osthoff; he argues from gelidus, which did not become *golidus, that the vowel before the weakening was /i/ and not /e/.^[2] Sihler reports that some have seen in the class the element *-eto-, which suits the meaning, but he objects that the voicing of /t/ in prehistoric Latin would be remarkable.^[3]

Earliest recorded meaning

Plautus, of about 250–184 BC,^[4] already has many, among them calidus (“hot”), liquidus (“clear”) and nitidus (“bright”).^[2] Naevius, of about 235–200 BC,^[4] has madidus (“drenched”) and timidus (“afraid”), the latter spelled ⟨-edus⟩.^[2][5]

Semantic evolution

Most words in -idus stand in a set with an abstract noun in -or and a stative verb in /-ēre/ or /-ēscere/, such as calidus beside calor and caleō, or timidus beside timor and timeō.^[2][3][5] Others are built on nouns, such as gelidus, herbidus and morbidus.^[5] The form rōscidus shows an enlargement in /-cidus/, perhaps after sūcidus.^[5]

Timeline

• c. 250–184 BC – Plautus uses calidus, liquidus, nitidus, squālidus and lepidus.^[2][4]
• c. 235–200 BC – Naevius uses madidus and timidus.^[2][4]
• 96–55 BC – Lucretius has lūcidus.^[2][4]

Meanings

Suffix

1. Forms adjectives of state or tendency, largely from intransitive verbs in /-ēre/: avidus, calidus, frīgidus, līvidus, timidus.^[5][1][3]
2. Forms adjectives from nouns: gelidus, herbidus, morbidus.^[5]

Word family

• avidus
• calidus
• frīgidus
• līvidus
• timidus
• gelidus
• herbidus
• morbidus
• rōscidus
• madidus
• liquidus
• nitidus
• rūbidus
• squālidus
• āridus
• lūcidus
• lepidus

Related words

• -or
• English -id

Usage notes

Syncope shortened some of these words: the OLD gives caldus beside calidus, and the Appendix Probi censures it in the pair calida non calda.^[5][6]

References

1. ^ a b c d e Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g Weiss, Michael (2020), Outline of the Historical and Comparative Grammar of Latin, 2nd ed., Ann Arbor: Beech Stave
3. ^ a b c Sihler, Andrew L. (1995), New Comparative Grammar of Greek and Latin, New York: OUP
4. ^ a b c d e Köbler, Gerhard (2010), Lateinisches Abkunfts- und Wirkungswörterbuch für Altertum und Mittelalter, online ed., koeblergerhard.de
5. ^ a b c d e f g Glare, P. G. W., ed. (2012), Oxford Latin Dictionary, 2nd ed., Oxford: Oxford University Press
6. ^ Appendix Probi, a late antique list of correct and censured Latin word forms ("calida non calda"); ed. H. Keil, Grammatici Latini IV, Leipzig 1864, 197–199.