ENGLISH
REFERENCE

longitudinal

adj.
C1 Advanced US //ˌɫɑndʒəˈtudənəɫ// UK //lˈɒndʒɪtjˌuːdɪnəl// lon·gi·tu·di·nal

adj. describing a study or observation that follows the same people or things over a long period of time. It can also describe something that runs lengthwise from top to bottom.

adj. relating to the observation of data or subjects over an extended duration to identify changes or trends; also describes a position or direction running lengthwise. Often used in academic research contexts or anatomical descriptions.


SIMPLE

The scientists conducted a longitudinal study on child development.

CONTEXTUAL

Researchers used a longitudinal approach to track how the patients' health changed over twenty years of treatment.

COMPLEX

The longitudinal analysis of the coastal ecosystem revealed gradual shifts in species distribution that were not apparent in shorter, cross-sectional observations conducted during the previous decade.

Origin

From Middle English longitudinal, from Latin longitūdin-, oblique stem of longitūdō (“length, longitude”). By surface analysis, longitude + -in- + -al.

Usage

Commonly modifies nouns like 'study', 'research', 'analysis', or 'section'.

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