What is the word for someone that uses other people? [duplicate]

Solution 1:

I would suggest leech:

2. a person who clings to another for personal gain, especially without giving anything in return, and usually with the implication or effect of exhausting the other's resources; parasite.

Solution 2:

There's parasite:

: a person or thing that takes something from someone or something else and does not do anything to earn it or deserve it
_{source: http://www.merriam-webster.com/dictionary/parasite}

Along the same lines are freeloader, sponge, and mooch:

freeload: to get or ask for things (such as food, money, or a place to live) from people without paying for them

sponge: someone who gets something from someone else without doing or paying anything in return

mooch: to ask for and get things from other people without paying for them or doing anything for them (noun form can be either "mooch" or "moocher")
_{All definitions from http://www.m-w.com}

Solution 3:

A parasite:

• One who habitually takes advantage of the generosity of others without making any useful return. (AHD)

or a sponger:

• a person who lives off other people by continually taking advantage of their generosity; parasite or scrounger

The Free Dictionary

Solution 4:

It is established in common dialect (Scottish - proper English) that a user is someone who uses another person to serve themselves heedlessly.

Simply using the word user might be straightforward enough! A word which springs to mind for me, due to my locale, is a skag - also someone who uses another person. Opportunist/parasite/freeloader.

Interestingly (some might say), skag also means Heroin. A skag (or skaghead) is a user (of Heroin), but the word spills over to refer to a person who takes advantages of others heedlessly. (Incidentally, it just so happens that long-term addicts of skag show tendency to display this behaviour).

Solution 5:

In popular vernacular this person is simply called a

user

And because it's popular vernacular I'll cite Urban Dictionary:

user (n.) - a person who uses a friend or aquaintance solely for the purposes of gaining a type of advantage; whether it be:

1) when no one else is around, they need someone (like you) to take them places

2) someone who doesn't include you in any activities that they have with their friends, who you too, are friends with, yet YOU would invite him or her in a heart beat

3) a person who completely ignores you when he or she is with a group of people who may be cooler than you

4) a person who can call you ANYTIME and you would be there for them, and yet if you try to call him or her, they will not pick up; however, ONLY for using purposes he or she would pick up, like if he or she needs a RIDE somewhere (yet they would pick up their phone for any other person)

5) a person who constantly gives you excuses...when you know he or she is completely full of SHIT

and even after all this, this person still calls you their "friend"