forty meaning
EN
[ˈfɔɹti] [ˈfɔɹɾi] [ˈfɑɹɾij] [-ɔː(ɹ)ti] 
US - NounPLfortiesPREfor-
- More Examples
- Used in the Middle of Sentence
- It’s a special order, so we can’t send it back; if the customer won’t accept it, we’ll have to eat the forty tons of steel ourselves.
- In each high-frequency (20 Hz) rTMS session, subjects received forty trains of 1.9 s duration, separated by an intertrain interval of 12 s (1560 pulses per session).
- He had taught school for forty years before retiring.
- Used in the Middle of Sentence
Definition of forty in English Dictionary
- Part-of-Speech Hierarchy
- Nouns
- Countable nouns
- Countable nouns
- Numerals
- Nouns
- en forty-five
- en forty-eight
- en forty-two
- en forty-four
- en forty-three
Source: Wiktionary
Grammatically, this word "forty" is a noun, more specifically, a countable noun. It's also a numeral.