plural of line up

A rollerblade: a roller skate with all wheels aligned in a single row along the sole for greater speed and maneuverability.

(manufacturing) A system of workers and machinery in which a product is assembled in a series of consecutive operations; typically the product is conveyed by a continuously moving belt

The altitude, in a mountainous region, above which the ground is covered with snow, at any particular time.

(nautical) A line for tightening the leech of a triangular mainsail to prevent it from fluttering.

A skater who uses in-line skates.

Skating using in-line skates.

(geometry) A part of a straight line bounded by two points.

A spectral line resulting from the emission of electromagnetic radiation from an atom or other species as it decays from an excited state to one of lower energy.

plural of main line