collimate

tr.v., -mat·ed, -mat·ing, -mates.

1. To make parallel; line up.
2. To adjust the line of sight of (an optical device).

[New Latin collīmāre, collīmāt-, alteration of Latin collīneāre, to aim : com-, intensive pref.; see com- + līneāre, to make straight (from līnea, line; see line¹).]

collimation col'li·ma'tion n.

(kol′imā′shən)
n

Literally, making parallel. In radiology, collimation refers to the elimination of the peripheral (more divergent) portion of a useful x-ray beam by means of metal tubes, cones, or diaphragms interposed in the path of the beam. See also diaphragm.

In microscopy, the process of making light rays parallel; the adjustment of two or more optical axes with respect to each other. In radiology, the restriction of the beam size to the area under investigation. This reduces the scattered radiation reaching the x-ray film and the exposure of attendants.

IN BRIEF: v. - Adjust the line of sight of (an optical instrument); Make or place parallel to something.

Tutor's tip: This word was used in the 2006 Scripps National Spelling Bee finals.