indifferent

American Heritage® Dictionary of the English Language, Fourth Edition

1. adj. Having no particular interest or concern; apathetic: indifferent to the sufferings of others.
2. adj. Having no marked feeling for or against: She remained indifferent toward their proposal.
3. adj. Not mattering one way or the other: It's indifferent to me which outfit you choose.
4. adj. Characterized by a lack of partiality; unbiased: an indifferent judge.
5. adj. Being neither too much nor too little; moderate.
6. adj. Being neither good nor bad; mediocre: an indifferent performance. See Synonyms at average.
7. adj. Being neither right nor wrong.
8. adj. Not active or involved; neutral: an indifferent chemical in a reaction.
9. adj. Biology Undifferentiated, as cells or tissue.

Century Dictionary and Cyclopedia

1. Without difference of inclination; not preferring one person or thing to another; neutral; impartial; unbiased; disinterested: as, an indifferent judge, juror, or arbitrator.
2. Feeling no interest, anxiety, or care; unconcerned; apathetic: as, a man indifferent to his eternal welfare.
3. Not making a difference; having no influence or preponderating weight; immaterial; of no account: as, it is indifferent which road we take.
4. Regarded without difference of feeling; not exciting special interest; uninteresting.
5. Falling short of any standard of excellence; of common or mediocre quality or kind; only passable or tolerable; ordinary.
6. In biology, undifferentiated; primitive; common; not specialized.
7. n. One who is indifferent or apathetic.
8. n. That which is indifferent or an object of indifference; that which affords no decisive ground of choice.

Wiktionary

1. adj. Not caring or concerned; uninterested, apathetic.
2. adj. Mediocre, usually used negatively in modern usage.
3. adj. Having no preference or bias, being impartial.
4. adj. Not significant in size or amount, immaterial.
5. adj. mechanics Being in the state of neutral equilibrium.
6. adv. obsolete To some extent, in some degree (intermediate between very and not at all); moderately, tolerably, fairly.

GNU Webster's 1913

1. adj. Not making a difference; having no influence or preponderating weight; involving no preference, concern, or attention; of no account; without significance or importance.
2. adj. Neither particularly good, not very bad; of a middle state or quality; passable; mediocre.
3. adj. Not inclined to one side, party, or choice more than to another; neutral; impartial.
4. adj. Feeling no interest, anxiety, or care, respecting anything; unconcerned; inattentive; apathetic; heedless.
5. adj. (Law) Free from bias or prejudice; impartial; unbiased; disinterested.
6. adv. obsolete To a moderate degree; passably; tolerably.

WordNet 3.0

1. adj. having only a limited ability to react chemically; chemically inactive
2. adj. being neither good nor bad
3. adj. marked by no especial liking or dislike or preference for one thing over another
4. adj. fairly poor to not very good
5. adj. characterized by a lack of partiality
6. adj. neither too great nor too little
7. adj. (often followed by `to') lacking importance; not mattering one way or the other
8. adj. showing no care or concern in attitude or action
9. adj. marked by a lack of interest
10. adj. (usually followed by `to') unwilling or refusing to pay heed