Uncompounded; pure; unmixed.
Not accompanied by anything else; one in number.
Designed for the use of only one.
Performed by one person, or one on each side.
Not divided in parts.
Not married, and (in modern times) not dating or without a significant other.
Having only one rank or row of petals.
A score of one point, awarded when a kicked ball is dead within the non-kicking team's end zone or has exited that end zone.
A bill valued at $1.
A 45 RPM vinyl record with one song on side A and one on side B.
A tile that has a different value (i.e. number of pips) at each end.
A single cigarette.
A one-way ticket.
A handful of gleaned grain.
A popular song released and sold (on any format) nominally on its own though usually having at least one extra track.
A shot of only one character.
A score of one run.
A game with one player on each side, as in tennis.
One of the reeled filaments of silk, twisted without doubling to give them firmness.
A floating-point number having half the precision of a double-precision value.
One who is not married or does not have a romantic partner.
A hit in baseball where the batter advances to first base.
To take the irregular gait called singlefoot.
To reduce (a railway) to single track.
To identify or select one member of a group from the others; generally used with out, either to single out or to single (something) out.
To thin out.
To get a hit that advances the batter exactly one base.
Not purified; impure