The digit/figure 2.
"He wrote the number two on his forehead to show he was listening."
In plain English: Two is the number that comes right after one and represents a pair of things.
"He ordered two beers for his friends."
A numerical value equal to 2; this many dots (••).
"She counted exactly two stars in the night sky, noting that there were only two visible through the clouds."
The word "two" comes from the Proto-Indo-European root *dwóh₁, which originally meant the number two. It traveled into English through Old English and Middle English forms like twā and twa.