(literary, archaic) The utmost extremity, especially of a fight; bodily harm or death.

of or relating to utility / (ethics) pertaining to utilitarianism / practical and functional, present for use, not just for show.

Someone who practices or advocates utilitarianism.

(now rare) Useful.

(economics) A theoretical unit of measure of utility, for indicating a supposed quantity of satisfaction derived from an economic transaction.

To make use of; to use. / To make useful; to find a practical use for. / To make best use of; to use to its fullest extent, potential, or ability.

completely, entirely, to the fullest extent

(Canada, US, Oxford British English) Alternative spelling of utilisation

Ideal but often impractical; visionary. / Of or pertaining to or resembling a utopia.

Someone who supports or heralds the establishment of a utopia.