enable

The sense the word was built for: Middle English enablen, en- plus able, literally "to make able." The King James Bible of 1611 uses it of strength given from above: "who hath enabled me." The usual frame is a person plus a to-infinitive, as in enable someone to do or to be something. Empower and endow are close, but enable keeps the stress on the ability itself rather than on authority or gift.

Where ability shades into opportunity, the subject is often a thing rather than a person. Joseph Addison in 1711 gives it to temperance, and The Economist in 2013 gives it to the gut microbiome. Two patterns run side by side: enable someone to do something, and enable something directly, as with sensors that "enable detailed analysis." Allow is the near synonym, though allow leans toward permission and enable toward means.

The everyday computing sense: a feature is switched on rather than given a power it lacked. Activate and turn on are its close synonyms, and disable is its fixed opposite. Where the circuit-pulse sense is about a signal reaching a component, this one is usually about a setting a person chooses, as when you enable two-factor authentication on an account.

Here the power given is permission rather than capacity. A law, a license or a certificate enables by authorizing, which is why permit and authorize sit so close. Drachinifel's Anti-Slavery Patrols (2018) speaks of "a direct law specifically enabling slavery." Contrast the "means and opportunity" sense, where the subject makes something possible without sanctioning it.

A sense with a moral edge. It uses the same frame as the "means and opportunity" sense, enabling someone to go on doing something, but here the help is the problem. It belongs to talk of addiction and codependency, where shielding a person from consequences lets the habit continue. Use it when the support itself is being criticized, not merely described.

In digital logic the enable is a control input. A flip-flop, register or buffer ignores its data until a qualifying pulse on that line puts it into action. Engineers use the word as a noun in enable line and enable signal, and the verb follows from it: the control line enables the register, and the clock pulse enables the latch.