| OFFASDYKE | A defensive earthwork along the Welsh border, stretching from the mouth of the Dee to that of the Severn |
| OFFA | A defensive earthwork along the Welsh border is named after this king of Mercia (4) |
| COTTONMOUTH | *Venomous reptile of the SE US |
| SECANT | In trigonometry, the ratio of the hypotenuse of a right-angled triangle to that of the adjacent side; the reciprocal of the cosine (6) |
| SINE | A trigonometric function that in a right-angled triangle is the ratio of the length of the opposite side to that of the hypotenuse |
| HAWKEBAY | Section of the eastern coast of the North Island of New Zealand stretching from the Mahia Peninsula in the northeast to Cape Kidnappers/Te Kauwae-a-Maui in the southwest |
| COSECANT | In geometry, the ratio of the length of the hypotenuse in a right-angled triangle to that of the opposite side (8) |
| WASPIE | A laced corset or girdled belt serving to cinch the waist of its wearer to proportions akin to that of the vespa from which its name derives (6) |
| LENS | A part of a camera that plays a role similar to that of the cornea (4) |
| KIEL | ____ Canal, artificial waterway that runs from the mouth of the River Elbe to the Baltic Sea (4) |
| BRAMBLING | With a name similar to that of the blackberry bush or a variety of cooking apple, a chaffinch-like bird, known regionally as cock o' the north, furze chirper and tartan back (9) |
| SUNDAE | With a name similar to that of the Christian Sabbath, a cherry-and-syrup-topped ice cream served in a tulip-shaped glass; or, a type of mixed nougat or other confection (6) |
| HILBRE | The ___ Islands, located at the mouth of the Dee estuary; accessible on foot during summer low tides (6) |
| HUMBOLDT | Name for the cold-water current of the southeast Pacific Ocean running along the western coast of South America. Except during El Nino periods, this current brings fog to the nearby coast but also hel |
| GREATWALL | Defensive structure constructed in the 3c B.C. stretching from the Yellow Sea to the central Asian d |
| OFCHINA | Defensive structure constructed in the 3c B.C. stretching from the Yellow Sea to the central Asian desert (5,4,2,5) |
| DENSER | Like the tree distribution of the Amazon, compared to that of the Sahara |
| NEUTRON | An uncharged elementary particle that has a mass nearly equal to that of the proton (7) |
| ABERDEEN | It's at the mouth of the Dee |
| DELTA | The mouth of the Dee? (5) |
