longitudinal

[lon-ji-tood-n-l, -tyood-]

adjective

1. of or relating to longitude or length.

   longitudinal measurement.

2. extending in the direction of the length of a thing; running lengthwise.

   a thin, longitudinal stripe.

3. Zoology.,  pertaining to or extending along the long axis of the body, or the direction from front to back, or head to tail.

4. pertaining to a research design or survey in which the same subjects are observed repeatedly over a period of time.

noun

1. a longitudinal framing member, as in the hull of a ship.

longitudinal

/ ˌlɒŋɡ-, ˌlɒndʒɪˈtjuːdɪnəl /

adjective

1. of or relating to longitude or length

2. placed or extended lengthways Compare transverse

3. psychol (of a study of behaviour) carried on over a protracted period of time

Other Word Forms

• longitudinally adverb

Word History and Origins

Origin of longitudinal¹

1535–45; < Latin longitūdin- (stem of longitūdō; longitude ) + -al ¹

Example Sentences

Marc was accepted into AllFTD, a longitudinal study that is the largest ever conducted for this disease.

From Los Angeles Times

And, given that botox only lasts three to six months, any longitudinal study would have to ensure participants are going for regular top-ups.

From BBC

The researchers looked at data from the Panel Study of Income Dynamics, which they noted is considered to be “gold standard longitudinal study of earnings and employment dynamics” in social sciences.

From Salon

The researchers found that the auroras had longitudinal structures that were aligned with magnetic field lines, the first time they had been identified in a low-latitude, blue-dominant aurora.

From Science Daily

The data used in this study was collected as part of the Childhood Development after Cochlear Implantation Study, a national, multi-site longitudinal study.

From Science Daily

Related Words

• lengthwise 
• long 
• long-term