two

Etymology

PIE word *dwóh₁ From Middle English two, twa, from Old English twā, feminine and neuter of twēġen (whence twain), from Proto-West Germanic *twai-, from Proto-Germanic *twai, from Proto-Indo-European *dwóh₁. Cognate with Scots twa (“two”); North Frisian tou, tuu (“two”); Saterland Frisian twäin, two (“two”); West Frisian twa (“two”); Dutch twee (“two”); Low German twee, twei (“two”); German zwei, zwo (“two”); Danish and Norwegian to (“two”); Swedish två, tu (“two”); Icelandic tvö (“two”); Latin duō (“two”); Ancient Greek δύο (dúo, “two”); Irish dhá (“two”); Lithuanian dù (“two”); Russian два (dva, “two”); Albanian dy (“two”); Old Armenian երկու (erku, “two”); Sanskrit द्व (dvá, “two”); Tocharian A wu, Tocharian B wi. Doublet of duo. See also twain.

num

1. A numerical value equal to 2; this many dots (••).
2. Describing a set or group with two elements.
   […]The two murders might have been done by one of the ryots who was dissatisfied over his assessment and thought he had a grievance. […]. 1927, F. E. Penny, chapter 5, in Pulling the Strings

noun

1. The digit/figure 2.
   The number 2202 contains three twos.
2. (US, informal) A two-dollar bill.
3. A child aged two.
   This toy is suitable for the twos and threes.
4. A playing card featuring two pips.
5. Two o'clock, either a.m. or p.m.