1. Indicating coincidence of high tides or low tides.
2. Of or relating to a line that passes through each location on a coastal map where tides occur at the same time of day.
(Navigation) (of a line on a tidal chart) joining points at which high tide occurs simultaneously
1. pertaining to a coincidence of tides.
2. (on a chart or map) indicating a line connecting points at which high tide occurs at the same time.