The digit or figure 1. / (mathematics) The neutral element with respect to multiplication in a ring. / (US) A one-dollar bill. / One o'clock, either a.m. or p.m.

Of a period of time, being particular. / Being a single, unspecified thing; a; any. / Sole, only. / Whole, entire. / In agreement. / The same. / Being a preeminent example.

To cause to become one; to gather into a single whole; to unite.

Others' circumstances seem more desirable than one's own but in reality often are not.

Alternative spelling of twenty-one

(modifying a numeral, one to twelve) In conjunction with a numeral, indicates the time within a twelve-hour period (midnight to noon or noon to midnight), specifically the time when the hour hand of a clock points precisely to the symbol or marking corresponding to the designated numeral.

The cardinal number one hundred plus one.

(historical) A nation in Eurasia that existed from December 30, 1922 to December 26, 1991.

Any of various Old World large owls of the genus Bubo, especially the Eurasian eagle owl, Bubo bubo, that have prominent ear tufts.

plural of degree of comparison