Selfish (adjective)

1. Concerned primarily with one's own interests, benefits, welfare, etc., regardless of others.
2. Lacking consideration for others; concerned chiefly with one's own personal profit or pleasure.
3. Characterized by or manifesting concern or care only for oneself.
4. Inclined to promote one's own interests or welfare.

Origin:

Early 18th century: from self + -ish.

Examples:

1. He is selfish and only thinks about himself.
2. She's so selfish, she never thinks about how her actions affect others.
3. He made a selfish decision that hurt many people.
4. She is selfish and only cares about her own needs.
5. He is selfish and never shares his toys with other children.