From BiblePortal Wikipedia

King James Dictionary [1]

MU'TUAL, a. L. mutuus, from muto, to change.

Reciprocal interchanged , each acting in return or correspondence to the other given and received. Mutual love is that which is entertained by two persons each for the other mutual advantage is that which is conferred by one person or another,and received by him in return. So we say, mutual assistance, mutual aversion.

And, what should most excite a mutual flame,

Your rural cares and pleasures are the same.

Webster's Dictionary [2]

(1): ( a.) Reciprocally acting or related; reciprocally receiving and giving; reciprocally given and received; reciprocal; interchanged; as, a mutual love, advantage, assistance, aversion, etc.

(2): ( a.) Possessed, experienced, or done by two or more persons or things at the same time; common; joint; as, mutual happiness; a mutual effort.

Vine's Expository Dictionary of NT Words [3]

 Romans 1:12Other