directrix (dÉªËrÉktrÉªks; daÉª-) n. 1. (Mathematics) geometry a fixed reference line, situated on the convex side of a conic section, that is used when defining or calculating its eccentricity. 2. (Professions) a directress [C17: New Latin, feminine of director] diâ¢recâ¢trix (dÉªËrÉk trÉªks, daÉª-)
e-Visa [edit]. Turkish e-visa can be obtained prior to arrival or on arrival (for a higher cost). Citizens of these countries are eligible to apply for a multiple entry e-Visa which allows to stay up to 90 days (unless otherwise stated):1  Antigua and Barbuda. 2  Armenia #. - Countries whose citizens are allowed to enter Turkey with their expired passports (up to 5 years). 3 - Allowed to enter Turkey with their passports or ID cards expired within the last year. Turkish e-visa can be obtained prior to arrival or on arrival (for a higher cost).
As of April 10, 2014, U.S. citizens who wish to visit Turkey for less than 90 days need to obtain Turkish visas online. Sticker visas will no longer be avaliable on arrival at airports and at the ports of entry.Please also see the information at the Embassy's new e-visa regulation's page. 2..S. citizens do typically need an e-visa to enter Turkey, but cruise ship passengers are permitted to come ashore without a visa for day visits by special arrangements. In short, you may visit Turkey on the day trip from your cruise ship without being in possession of your passport.