ūsˈable or ūseˈable adjective

ūsˈableness, ūseˈableness, ūsabilˈity or ūseabilˈity noun

ūsˈably or ūseˈably adverb

used /ūzd/ adjective

1. Already made use of
2. Second-hand
3. Experienced, expert (Scot)
4. Usual, customary (obsolete)
5. /ūst/ accustomed, habituated (with to, or (old Scot) in or with)

ūˈser noun

1. A person who uses
2. A person who takes drugs, a drug addict (informal)
3. Continual enjoyment of a right (cf non-user; Fr user)
4. A right established by long use (law)

use-by date noun

A date, indicated on a manufacturer's or distributor's label, after which goods, esp foods, are considered no longer fit for use (also figurative)

used-upˈ adjective

Exhausted

user-friendˈly adjective

1. (of a computer or software item) designed to be easily understood and operable by non-specialists, guiding the user by means of clear instructions and menus, etc
2. (generally, of any product, etc) designed with the ease of the user in mind, deliberately not off-putting

user interface noun

The means of communication between a computer system and the user

ūˈsername or user ID noun

The name or code by which a person or group is identified when gaining access to a computer network

I could use (informal)

I would feel better for, I want, need

use up

1. To consume
2. To exhaust
3. To tire out