Sorry, it's HTTP Live Streaming. I don't know much about it but this part on Wikipedia seems relevant:
It resembles MPEG-DASH in that it works by breaking the overall stream into a sequence of small HTTP-based file downloads, each download loading one short chunk of an overall potentially unbounded transport stream.
Sounds like this might mean trouble for use with Pihole. My kodi log entries looks like this:
16:25:29.130 T:1473766384 INFO: ffmpeg[57D7E3F0]: [hls,applehttp] Opening 'https://video-edge-c681d8.arn03.hls.ttvnw.net/v1/segment/CtgCsTZ1tvspmlCBOETskg3aQiLZHtH1lGELC92TQkVBGOiRF8ZrO6PCWbgS0XzedjcM9Hrte1gvs_r473OC5G3_G8CSOZfrjIqVZPvETdcV_FAu9DKrYidusrY3OplCSpgtCmIujvtKnUByYs1QMkOeo7tkvkH50EFBc10j2tqPqg9dgEXmVEzA0Nu45QN320vCFZC6sdp4PRUycb6AQwnll0ZbrNKOEpDK4Tnu8kJiGSRrZJye4qBpEBUk_LZjQ2xlroRl1Zqw_x4xSJ_A8wvj0wSZnLUxYgsNrlRvF_WLPgYBPCvoBVZMhy-2j9hVY74gVvISLhl5NXPlVzQr52kNxRdWv21M2ju9Q-kOtvOBWt589wTio8gUkwWxYs6jQWjGU2FdeZLO84dQr3lJoDn_4gHPlpBMI-KrdrZft_X90HakR_d0tCHBbcHZdAonrYKfWdr3KmzgkA8SEHw6V09MaVgMpMhmuxEW8XQaDEvs4ZhGqmXvnZzuNw.ts' for reading
16:25:31.396 T:1473766384 INFO: ffmpeg[57D7E3F0]: [hls,applehttp] Opening 'https://video-edge-c681d8.arn03.hls.ttvnw.net/v1/segment/CtgChq3cFGlGfLDoFdAGDJ5BM822rueZ0GhRk_EJQjy3bAs1uYOdfK2IqULQFauLaNnQ5vcY_Zj8AWt7AGALfue_ngipke-3rbupRxyPz05p9_ipJwQWNuQfg64bizAjqyaoSNyEksSaHS0YX7IsCxsq4McUS-BTyFKWQK6TZr6MW-A-piEks8YhAlbpIkcZRbSZsIiaAa9yaXZkndtw9cUITT1fe4Psp6R_COGJEVSeoMOWNYc4k5f9ozDDyOJV511Qh-JCCumQRFgvex2PxJB1FxnBr66r6hBB78wWBG2r2ZvluOHj1zb18s-Mh1tYqqnVyk9J0EKRy9y-V_A7J-ssVXXXdbmsvV5eeN5HvrUD6f0lclWkuvIQAz3yrR77NrTzuqFWhZPh8DZJN_RdsmgdZHwYIdVrLdg8kjtG5Qx5PFoVWTSTwS1rZG253D6flaqrH2E2VdOkG7QSEPmzJ1WF5PIfuVPmA7qxO94aDBAQB-z0ZQW1Vl8_7w.ts' for reading
It seems there's a DNS query for each of these. I'm not sure if that's normal or if there's a malfunction within the add-on or Kodi. Either way it doesn't have anything to do with Pihole.
I don't really mind if these entires are put into the long-term database but the acute problem is them filling up pihole.log. I'll try to figure out how to make a script that deletes these entries.