lase

To lase most often means to produce laser light or to use a laser on something such as skin, metal, or another material. You might read that a device begins to lase when it starts giving off a steady laser beam, or that a doctor lased a small area during treatment. In modern English, this is the main meaning. The word also has older, now archaic uses. In earlier writing, lase could appear as a form of lace, meaning a narrow cord or strip, and in some old texts it could also stand for last, meaning to endure or continue.

The verb lase shows how a modern technical word can settle naturally into everyday English. It comes from laser and means, first of all, to produce coherent light by laser action. In scientific and technical writing, you may see sentences such as "the crystal began to lase" or "the system is designed to lase at a particular wavelength." From there, the verb is also used more broadly for applying a laser to something, especially in medicine or manufacturing. A surgeon may lase tissue during a procedure, and a machine may lase a surface to cut, mark, or treat it.

But the story does not end with lasers. In older English, lase also appeared as an archaic form related to lace. In that historical sense, it could refer to a narrow cord, band, or strip, especially in clothing or decoration. This use belongs to older stages of the language and is no longer part of normal modern usage.

There is also an old variant linked to last, where lase could mean to endure or continue. That meaning is entirely archaic now, but it can appear in historical texts. A modern reader is unlikely to meet it outside older literature or specialized reference works.

So today, if someone uses lase, they almost always mean the modern laser-related verb. The older meanings survive mainly as historical spellings and dictionary notes. That contrast gives the word an unusual shape: in present-day English it belongs to the world of light, precision, and technology, while in older English it leaves faint traces in the language of cloth and endurance.