An observation about the early stage of speciation, stating that if in a species hybrid only one sex is inviable or sterile, that sex is more likely to be the heterogametic sex.

Alternative form of rulebound

(rare, especially in the context of sexuality) Alternative letter-case form of Lesbian rule

(rare) A flexible leaden mason's rule that can be bent around the curves of a molding, and thus used to measure or reproduce irregular curves.

(transitive) To draw a line underneath, for example to mark the end of a topic or of an accounting period.

(military, law enforcement, chiefly in the plural) An internal rule among a military, police, etc. force defining the circumstances in which and manner with which to use force.

Alternative letter-case form of L'Hôpital's rule

Alternative letter-case form of L'Hôpital's rule

Alternative letter-case form of L'Hôpital's rule

(mathematics) A method of finding an approximate value for a definite integral, based on dividing the area under the graph of the function into a series of strips, each of which is approximately a trapezoid, and summing the area of all the trapezoids to approximate the area.