The Emoji library seems to base the metadata on Unicode's database, however it may not be descriptive enough for some. - https://www.wikiwand.com/en/Dingbat#/Dingbats_Unicode_block - Ticks - Crosses - Enclosed Text - Stars - Arrows - https://www.wikiwand.com/en/Emoticons_(Unicode_block) - Emotion (variations, whether it is positive or negative) - https://www.wikiwand.com/en/Miscellaneous_Symbols - Stars - Religious Symbols - Astrological Symbols - Music Symbols - Weather Symbols - https://www.wikiwand.com/en/Miscellaneous_Symbols_and_Pictographs - Hand Gestures - Weather Symbols - Geographic Symbols - Speech Symbols - (Other DIgital Pictographs) - https://www.wikiwand.com/en/Supplemental_Symbols_and_Pictographs - Animals - Emotion (variations, whether it is positive or negative) - Food and Drink - (Other Activity Pictographs) - https://www.wikiwand.com/en/Symbols_and_Pictographs_Extended-A - https://www.wikiwand.com/en/Transport_and_Map_Symbols - Transport Symbols - https://www.wikiwand.com/en/Arrows_(Unicode_block) and https://www.wikiwand.com/en/Supplemental_Arrows-B - Arrows - https://www.wikiwand.com/en/Enclosed_Alphanumerics and https://www.wikiwand.com/en/Enclosed_CJK_Letters_and_Months and https://www.wikiwand.com/en/Enclosed_Alphanumeric_Supplement - Enclosed Text - https://www.wikiwand.com/en/Geometric_Shapes and https://www.wikiwand.com/en/Geometric_Shapes_Extended - Squares - Triangles - Circles - Darkness/Lightness - Stars - Colors - https://www.wikiwand.com/en/Miscellaneous_Symbols_and_Arrows - Squares - Circles - Triangle - Arrows - Lightness/Darkness
The Emoji library seems to base the metadata on Unicode's database, however it may not be descriptive enough for some.