Numerous means there are a lot of them. Numerous complaints, numerous attempts, numerous small islands off the coast — it says many, in a slightly raised voice.
The word belongs to writing more than to speech. In conversation you say lots of or loads of, and save numerous for a report, a letter or a news story. It goes only with things you can count, and only in the plural: numerous mistakes, never numerous furniture and never numerous water. Two phrases carry it about: on numerous occasions, and too numerous to mention. The adverb numerously exists and is best left alone.
Numerous comes from Latin numerōsus, from numerus, 'number'. The Latin adjective did more than count: it also meant harmonious, because numerus covered rhythm and measure as well as quantity. English kept the counting half and let the music go.
Proto-Indo-European
*nem-
Latin
numerōsus — numerous, abundant; harmonious
Middle English
numerous
English, today
numerous
Built from
From Middle English numerous from Latin numerōsus (“numerous, abundant; harmonious”), from numerus (“number”). a doublet of numerose. Analyzeable as numero- + -ous.
Etymology from Wiktionary, CC BY-SA
Practised in A Man Called Ove, Numbers & Measurement
First appears in chapter 30 of A Man Called Ove.
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