(mathematics) Of a function, associating a unique value of its range with each value of its domain.

(chemistry) A covalent bond in which one electron pair is shared between two atoms.

(medicine) Pneumonia affecting one lung.

(of a line or queue) One person wide.

In a line or queue one person wide.

A line or queue one person wide.

Alone; without assistance; by oneself.

Without help from others; unassisted. / Using only one hand. / Designed for only one hand.

In a single-handed manner.

To type (or format) text without leaving a blank line between each line of text. / To type (or format) text with only one space between consecutive sentences.