-plus

Forms

-plus (feminine -pla, neuter -plum); first/second-declension suffix^[1]

Etymology

It is inherited from Proto-Italic *-plos, inherited from Proto-Indo-European *-pl(H)-o-.^[1][2] De Vaan reconstructs Proto-Italic *dwiplo-, which became ⟨duplo-⟩, since Italic replaced ⟨dui-⟩ by ⟨du-⟩ in compounds with “two”, as in duplex.^[2]

The root is uncertain.^[2] Proto-Indo-European *pleh₁- (“to fill”) suits manipulus “a handful”, if it is from ⟨manu-plo-⟩, but fits the numerals less well;^[2] Lindner proposes a root “to fold”, and de Vaan mentions a root “to approach” (“in two goes” > “double”), which he calls speculative.^[2]

Cognate with Umbrian tupler (“two at a time”), Ancient Greek διπλόος (diplóos, “double”), ἁπλόος (haplóos, “single, simple”) and Old Irish díabul (“double”).^[2]

Earliest recorded meaning

Plautus has simplus and duplus;^[2] quadruplus and dupliō “twice the amount” appear in the Twelve Tables.^[2]

Semantic evolution

The suffix makes multiplicative adjectives, “-fold”, from numerals: simplus “single”, duplus “double”, triplus “triple”, quadruplus “fourfold”.^[2][1] From these come verbs and nouns such as quadruplāre “to quadruple” and quadruplātor, one who brings a criminal accusation, both in Plautus.^[2]

Meanings

Suffix

1. -fold, times: forms multiplicative adjectives from numerals, as in simplus, duplus, triplus.^[1][2]

Word family

• simplus
• duplus
• triplus
• quadruplus

Related words

• duo
• duplex
• manipulus

References

1. ^ a b c d e f Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k de Vaan, Michiel (2008), Etymological Dictionary of Latin and the other Italic Languages, Leiden Indo-European Etymological Dictionary Series 7, Leiden; Boston: Brill