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Webster 1913 Edition

adv.

In the direction of length.

adv.

In the direction of length.

Some of the fibers of the human body are placed longitudinally, others transversely.

longitudinally ‎(comparative more longitudinally, superlative most longitudinally)

Along lines of longitude, in the direction from pole to pole, meridianally.
(sciences and social sciences) By sampling data over time rather than merely once.

along lines of longitude

by sampling over time