e·lon·ga·tion 
(ĭ-lông′gāshən, ĭ-lŏng′-, ē′lông-, ē′lŏng-)
(ĭ-lông′gāshən, ĭ-lŏng′-, ē′lông-, ē′lŏng-)n.
1. The act of elongating or the condition of being elongated.
2. Something that elongates; an extension.
3. Astronomy The angular distance between two celestial bodies as seen from a third body, typically Earth.