Expressio

Lat. [from exprimere, to express.] Expression; distinct mention in words or writing. Expressio eorum quae tacite insunt nihil operatur. The expression or express mention of those things which are tacitly implied, avails nothing.

2 Inst. 365.

Words used to express what the law will imply without them, are mere words of abundance.

6 Co. 11.

Thus, if land be let to two persons for the term of their lives, this creates a joint tenancy; and if the words "and the survivor of them" are added, they will be mere surplusage, because, by law, the term would go to the survivor.

Co. Litt. 191 a. 4 B. & Ald. 306. Broom's Max. 286.

Expressio unius est exclusio alterius

The expression of one thing is the exclusion of another. The express mention of one thing [person or place] implies the exclusion of another. See Designatio unius est exclusio alterius. This is a leading maxim in the construction of deeds, and the foundation of the rule that an implied covenant is in all cases controlled within the limits of an express covenant.

4 Co. 80 b.

Broom's Max. 278, 279, and note. It is a maxim also in the construction of statutes.

Story, J., 3 Story's R. 87, 89.

But it has been held not to apply in construing the Constitution of the United States.

Federalist, No. 83.

For other applications of this maxim, see 1 Story's Eq. Jur. § 102.

Story on Bailm. § 650. Story on Partn. § 209. Shaw, C. J., 2 Metcalf's R. 234, 241.