Deleting terms from the WordPress wp terms table

Use this: wp_delete_term

Edit:
Did a little dig around. With custom taxonomies, if you delete the term, the posts will not be assigned a new one. With ‘category’, whichever you set as the default from ‘Writing Settings’ will be assigned to the post. Besides, if you want to set the default category from code, use update_option('default_category', '<category name>'). There’s a third argument with wp_delete_term, using which you can force a default category, but I really couldn’t find how to use this argument.
(Ref: ../wp-includes/taxonomy.php, l. no. 1681)

Related Posts:

  1. Show posts without term
  2. Why is my WP_Query not working when tax_query terms are an array?
  3. Get list of posts which have at least one term from a custom taxonomy with WP_Query
  4. List taxonomy terms plus their latest post ordered by post date
  5. Get random terms
  6. WP Query for Posts (Products) in Specific Category that has 2 Specific Tags (*AND* both tags not *OR*)
  7. Order terms inside a select dropdown
  8. Add a default meta_value to new posts
  9. Get array of current post term ID’s
  10. How to add terms to my tax_query based off of the current post
  11. Change default ordering of taxonomy terms – pre_get_terms
  12. Empty tax_query array returns an empty array
  13. Pass array of taxonomy terms to wp_query
  14. Get list of terms that have posts in another term
  15. Formulate a url to show posts with both taxonomy terms
  16. Taxonomy search/filter with multiple taxonomies and multiple taxonomy terms
  17. Order by slug in get_terms with multiple taxonomies
  18. WordPress Related Post by tags in Single.php
  19. Function get_queried_object() return NULL in custom taxonomy
  20. Querying on multiple taxonomies pulled from $_GET checkbox array not working?
  21. List custom taxonomy terms sharing posts with a term from a second custom taxonomy
  22. Return Taxonomy/Term Information with Posts (WP_Query/get_posts)
  23. Get authors by term id or slug
  24. How to order posts by title after they have already been sorted by category
  25. WordPress query with items from more than one selfdefined taxonomy as `term` argument
  26. Taxonomy order exception for specific term
  27. Filter Custom Taxonomy Posts
  28. Get posts from multiple tax terms
  29. How to Order a list of taxonomies? orderby?
  30. get_the_terms – but only show 4 Posts
  31. Count posts per taxonomy else change taxonomy if less than x number
  32. How to add custom meta to ‘pre_get_terms’?
  33. get term id from term name
  34. WP_Query to output chosen term and posts with no term assigned
  35. WP Job Manager plugin – Listing only the twelve job categories on frontpage order by jobs they have
  36. Getting the post terms ‘wp_get_post_terms’ per post when within the functions.php file
  37. How to print term name inside wp post loop
  38. Using WP_Query for categories instead of get_terms
  39. Check if a post has term inside loop
  40. Grabbing taxonomy terms and inserting them into an array
  41. Create one-use post dynamically, add to main query, do not insert post (user profile view)
  42. Can’t get term id for category archive
  43. How can I do a orderby by the number of items? So basically list by starting with the array with the largest number of post
  44. How to make a post with certain taxonomy term display first before other post with only one query?
  45. How can I order a post query’s results based on the number of matching taxonomy terms?
  46. Only show tag with the same id as the post
  47. display ACF repater field in archive page
  48. Save queried result into database
  49. WP Query by 4 different taxonomies
  50. wp_set_object_terms() custom taxonomy not working correctly when using insert post
  51. Get categories within specific term
  52. How to display Woocommerce products list by tag
  53. wp_insert_post with ACF Fields and WP Meta Query returns no rows until update
  54. taxquery taxonomy get terms
  55. get term objects and post objects in query
  56. How to show terms from another taxonomy
  57. How to define a custom hierarchy for terms?
  58. Wrote a WP Cron Plugin and it triggers a fatal error upon activation
  59. Add a custom variable to query page object
  60. How to get several fields from wp_query?
  61. query only direct child and sub-terms of a current term archive
  62. Get access to all terms associated to each post that the wp_query loop displays
  63. How can I get taxonomy term name using term slug & post ID using build in WordPress function or class?
  64. I need to get all categories from a WP_Query
  65. taxonomy-{term}.php terms pagination returning 404 after a certain page
  66. Modify WordPress Search
  67. What kind of object type is WP_Query?
  68. Show two random posts from custom post type
  69. Duplicate Queries
  70. Counting number of posts with Category B in Category A
  71. pagination doesn’t show up for custom post type
  72. How to modify query so it grabs only 90 posts in total?
  73. Placing a div or img in between a post array using WP Query [closed]
  74. How to query ‘posts_per_page’ to display a different blog posts index template?
  75. Trying to check and see if a post has a featured image outside of the main loop
  76. Using pre_get_posts on a specific core/query block
  77. Efficient way to update multiple post meta
  78. How to use Meta Value Compare in WP_Query For Max and Min numbers
  79. Get number of authors
  80. Wp_query Add specific pending posts
  81. meta_query not working as expected
  82. exclude a post from wp_query loop
  83. Is_single() conditional tag returns null in query
  84. Is it possible to query a custom field where the value is between two fields?
  85. WP_Query args to show posts from specific custom taxonomy
  86. filter wp_query result with custom field values
  87. All blog data on a page using custom query gives 404 for page 2 and onward
  88. construct complex queries with WP User Query
  89. How do I fit WP_Query arguments into a function?
  90. Date not appearing in custom query
  91. Custom post type – filter content by custom meta box content
  92. Trying to output content from page, works locally but not online
  93. Custom order of posts in wp_query and different taxonomies
  94. Is meta_key used for ordering, filtering, or both?
  95. compare for multiple meta values for same key in wp_query
  96. Taxonomy Terms That Don’t Exist Display Results
  97. Add pagination to table generated by wp_query
  98. using next-page and previous page inside a wp_query
  99. restrict posts per page
  100. WordPress extremely slow when using get_posts with multiple meta_query relations