Indeed. Most of the matches for "retard" have the meaning of "delay":

  $ git grep -i retard v6.15
  v6.15:drivers/net/dsa/sja1105/sja1105_dynamic_config.c:/* The switch is so retarded that it makes our command/entry abstraction
  v6.15:drivers/net/wireless/broadcom/b43/phy_a.h:#define B43_OFDMTAB_ADVRETARD  B43_OFDMTAB(0x09, 0)
  v6.15:drivers/net/wireless/broadcom/b43/phy_lp.h:#define B43_LPPHY_ADVANCEDRETARDROTOR_ADDR B43_PHY_OFDM(0x8B) /* AdvancedRetardRotor Address */
  v6.15:drivers/net/wireless/broadcom/b43/phy_n.h:#define B43_NPHY_PHYSTAT_ADVRET   B43_PHY_N(0x1F3) /* PHY stats ADV retard */
  v6.15:drivers/net/wireless/broadcom/b43/tables.c:const u32 b43_tab_retard[] = {
  v6.15:drivers/net/wireless/broadcom/b43/tables.c: BUILD_BUG_ON(B43_TAB_RETARD_SIZE != ARRAY_SIZE(b43_tab_retard));
  v6.15:drivers/net/wireless/broadcom/b43/tables.h:#define B43_TAB_RETARD_SIZE 53
  v6.15:drivers/net/wireless/broadcom/b43/tables.h:extern const u32 b43_tab_retard[];
  v6.15:drivers/net/wireless/broadcom/b43/wa.c:static void b43_wa_art(struct b43_wldev *dev) /* ADV retard table */
  v6.15:drivers/net/wireless/broadcom/b43/wa.c: for (i = 0; i < B43_TAB_RETARD_SIZE; i++)
  v6.15:drivers/net/wireless/broadcom/b43/wa.c:   b43_ofdmtab_write32(dev, B43_OFDMTAB_ADVRETARD,
  v6.15:drivers/net/wireless/broadcom/b43/wa.c:    i, b43_tab_retard[i]);
  v6.15:drivers/net/wireless/broadcom/b43legacy/ilt.c:const u32 b43legacy_ilt_retard[B43legacy_ILT_RETARD_SIZE] = {
  v6.15:drivers/net/wireless/broadcom/b43legacy/ilt.h:#define B43legacy_ILT_RETARD_SIZE 53
  v6.15:drivers/net/wireless/broadcom/b43legacy/ilt.h:extern const u32 b43legacy_ilt_retard[B43legacy_ILT_RETARD_SIZE];
  v6.15:drivers/net/wireless/broadcom/b43legacy/phy.c:  for (i = 0; i < B43legacy_ILT_RETARD_SIZE; i++)
  v6.15:drivers/net/wireless/broadcom/b43legacy/phy.c:           b43legacy_ilt_retard[i]);
  v6.15:drivers/net/wireless/broadcom/b43legacy/phy.h:#define B43legacy_OFDMTAB_ADVRETARD B43legacy_OFDMTAB(0x09, 0)
  v6.15:drivers/net/wireless/broadcom/brcm80211/brcmsmac/d11.h:/* Advance Retard */
  v6.15:fs/bcachefs/bkey_cmp.h: /* we shouldn't need asm for this, but gcc is being retarded: */