two

occurring every two years

occurring twice a year

a sign of identity usually formed of the combined initials of a name

a succession of syllables, words, or sentences in one unvaried key or pitch

a single rail serving as a track for a wheeled vehicle

exclusive ownership through legal privilege, command of supply, or concerted action

uttered or sounded in one unvarying tone : marked by a sameness of pitch and intensity

identity in musical pitch or the writing, playing, or singing of parts in a musical passage at the same pitch or in octaves

the entire celestial cosmos

an eyeglass for one eye

consisting of two parts or elements or having two like parts

being the only one

tedious sameness or sameness of tone or sound

the act or process of duplicating. 

an institution of higher learning providing facilities for teaching and research and authorized to grant academic degrees

a handheld optical instrument composed of two telescopes and a focusing device and usually having prisms to increase magnifying ability

to put together to form a single unit

to make into a unit or a coherent whole