Here is a list of all documented struct and union fields with links to the struct/union documentation for each field:

w : ctx_query
wait : tcp_send_list
wait_limit : config_file
wait_limit_cookie : config_file
wait_limit_cookie_netblock : config_file
wait_limit_netblock : config_file
wait_limits_cookie_netblock : fast_reload_construct, infra_cache
wait_limits_netblock : fast_reload_construct, infra_cache
wait_prime_ta : val_qstate
wait_priming_stub : iter_qstate
wait_subquery : subnet_qstate
wait_subquery_done : subnet_qstate
wakeup_timer : dt_msg_queue
wakeup_timer_enabled : dt_io_thread
wakeup_timer_lock : dt_io_thread
want_dnssec : serviced_query
want_quit : libworker
want_to_exit : dt_io_thread
want_to_exit_flush : stop_flush_info
want_to_quit : outside_network
was_ratelimited : module_qstate, ub_result
whitelist : ipsecmod_env, subnet_env
why_bogus : ub_result
winsock_register_wsaevent : ub_event_base_vmt
winsock_tcp_wouldblock : ub_event_vmt
winsock_unregister_wsaevent : ub_event_vmt
worker : cache_lookup_info, daemon_remote, del_info, dump_info, fast_reload_printq, fast_reload_thread, module_env
worker_allocs : daemon
worker_base : module_env
workers : daemon
write_wait_first : reuse_tcp
write_wait_prev : waiting_tcp
write_wait_queued : waiting_tcp