¦ cardinal number equivalent to the sum of one and one; one less than three; 2. (Roman numeral: ii or II.)
Phrases
put two and two together draw an obvious conclusion from what is known or evident.
that makes two of us informal that is true of me also.
two by two (or two and two) side by side in pairs.
two can play at that game informal used to assert that one is equally capable of copying another's strategy, to their disadvantage.
two cents (or two cents' worth) N. Amer. informal an unsolicited opinion.
two's company, three's a crowd two people, especially lovers, should be left alone together.
Derivatives
twofold adjective & adverb
Origin
OE twa (fem. and neut.) of Gmc origin.