diff --git a/src/attack.c b/src/attack.c
index 8f258ea..0a8e583 100644
--- a/src/attack.c
+++ b/src/attack.c
@@ -52,11 +52,11 @@ bool sq_is_attacked(const pos_t *pos, const bitboard_t occ, const square_t sq, c
      */
 
     /* bishop / queen */
-    if (hyperbola_bishop_moves(occ, sq) & (pos->bb[c][BISHOP] | pos->bb[c][QUEEN]))
+    if (hq_bishop_moves(occ, sq) & (pos->bb[c][BISHOP] | pos->bb[c][QUEEN]))
         return true;
 
     /* rook / queen */
-    if (hyperbola_rook_moves(occ, sq) & (pos->bb[c][ROOK] | pos->bb[c][QUEEN]))
+    if (hq_rook_moves(occ, sq) & (pos->bb[c][ROOK] | pos->bb[c][QUEEN]))
         return true;
 
     /* knight */
@@ -137,7 +137,7 @@ bitboard_t sq_attackers(const pos_t *pos, const bitboard_t occ, const square_t s
 
     /* bishop / queen */
     to = pos->bb[c][BISHOP] | pos->bb[c][QUEEN];
-    tmp = hyperbola_bishop_moves(occ, sq) & to;
+    tmp = hq_bishop_moves(occ, sq) & to;
     attackers |= tmp;
 #   ifdef DEBUG_ATTACK_ATTACKERS
     bb_print("att bishop/queen", tmp);
@@ -145,7 +145,7 @@ bitboard_t sq_attackers(const pos_t *pos, const bitboard_t occ, const square_t s
 
     /* rook / queen */
     to = pos->bb[c][ROOK] | pos->bb[c][QUEEN];
-    tmp = hyperbola_rook_moves(occ, sq) & to;
+    tmp = hq_rook_moves(occ, sq) & to;
     attackers |= tmp;
 #   ifdef DEBUG_ATTACK_ATTACKERS
     bb_print("att rook/queen", tmp);
diff --git a/src/hyperbola-quintessence.c b/src/hyperbola-quintessence.c
index cb11501..5cf5589 100644
--- a/src/hyperbola-quintessence.c
+++ b/src/hyperbola-quintessence.c
@@ -95,7 +95,7 @@ void hyperbola_init()
  *
  * @Return: bitboard of @piece available pseudo-moves.
  */
-bitboard_t hyperbola_rank_moves(bitboard_t occ, square_t sq)
+bitboard_t hq_rank_moves(bitboard_t occ, square_t sq)
 {
     u32 rank = sq & SQ_RANKMASK;
     u32 file = sq & SQ_FILEMASK;
@@ -122,7 +122,7 @@ bitboard_t hyperbola_rank_moves(bitboard_t occ, square_t sq)
  *
  * @Return: bitboard of piece available pseudo-moves.
  */
-bitboard_t hyperbola_moves(const bitboard_t pieces, const square_t sq,
+bitboard_t hq_moves(const bitboard_t pieces, const square_t sq,
                                    const bitboard_t mask)
 {
     bitboard_t o = pieces & mask;
@@ -141,9 +141,9 @@ bitboard_t hyperbola_moves(const bitboard_t pieces, const square_t sq,
  *
  * @Return: bitboard of piece available pseudo-moves on its file.
  */
-bitboard_t hyperbola_file_moves(const bitboard_t occ, const square_t sq)
+bitboard_t hq_file_moves(const bitboard_t occ, const square_t sq)
 {
-    return hyperbola_moves(occ, sq, bb_sqfile[sq]);
+    return hq_moves(occ, sq, bb_sqfile[sq]);
 }
 
 /**
@@ -153,9 +153,9 @@ bitboard_t hyperbola_file_moves(const bitboard_t occ, const square_t sq)
  *
  * @Return: bitboard of piece available pseudo-moves on its diagonal.
  */
-bitboard_t hyperbola_diag_moves(const bitboard_t occ, const square_t sq)
+bitboard_t hq_diag_moves(const bitboard_t occ, const square_t sq)
 {
-    return hyperbola_moves(occ, sq, bb_sqdiag[sq]);
+    return hq_moves(occ, sq, bb_sqdiag[sq]);
 }
 
 /**
@@ -165,9 +165,9 @@ bitboard_t hyperbola_diag_moves(const bitboard_t occ, const square_t sq)
  *
  * @Return: bitboard of piece available pseudo-moves on its anti-diagonal.
  */
-bitboard_t hyperbola_anti_moves(const bitboard_t occ, const square_t sq)
+bitboard_t hq_anti_moves(const bitboard_t occ, const square_t sq)
 {
-    return hyperbola_moves(occ, sq, bb_sqanti[sq]);
+    return hq_moves(occ, sq, bb_sqanti[sq]);
 }
 
 /**
@@ -177,9 +177,9 @@ bitboard_t hyperbola_anti_moves(const bitboard_t occ, const square_t sq)
  *
  * @Return: bitboard of bishop available pseudo-moves.
  */
-bitboard_t hyperbola_bishop_moves(const bitboard_t occ, const square_t sq)
+bitboard_t hq_bishop_moves(const bitboard_t occ, const square_t sq)
 {
-    return hyperbola_diag_moves(occ, sq) | hyperbola_anti_moves(occ, sq);
+    return hq_diag_moves(occ, sq) | hq_anti_moves(occ, sq);
 }
 
 /**
@@ -189,9 +189,9 @@ bitboard_t hyperbola_bishop_moves(const bitboard_t occ, const square_t sq)
  *
  * @Return: bitboard of rook available pseudo-moves.
  */
-bitboard_t hyperbola_rook_moves(const bitboard_t occ, const square_t sq)
+bitboard_t hq_rook_moves(const bitboard_t occ, const square_t sq)
 {
-    return hyperbola_file_moves(occ, sq) | hyperbola_rank_moves(occ, sq);
+    return hq_file_moves(occ, sq) | hq_rank_moves(occ, sq);
 }
 
 /**
@@ -204,7 +204,7 @@ bitboard_t hyperbola_rook_moves(const bitboard_t occ, const square_t sq)
  *
  * @Return: bitboard of queen available pseudo-moves.
  */
-bitboard_t hyperbola_queen_moves(const bitboard_t occ, const square_t sq)
+bitboard_t hq_queen_moves(const bitboard_t occ, const square_t sq)
 {
-    return hyperbola_bishop_moves(occ, sq) | hyperbola_rook_moves(occ, sq);
+    return hq_bishop_moves(occ, sq) | hq_rook_moves(occ, sq);
 }
diff --git a/src/hyperbola-quintessence.h b/src/hyperbola-quintessence.h
index 82c867c..1657d50 100644
--- a/src/hyperbola-quintessence.h
+++ b/src/hyperbola-quintessence.h
@@ -11,23 +11,23 @@
  *
  */
 
-#ifndef _HYPERBOLA_QUINTESSENCE_H
-#define _HYPERBOLA_QUINTESSENCE_H
+#ifndef _HQ_H
+#define _HQ_H
 
 #include "board.h"
 #include "bitboard.h"
 
 void hyperbola_init(void);
 
-bitboard_t hyperbola_rank_moves(const bitboard_t occ, const square_t sq);
-bitboard_t hyperbola_moves(const bitboard_t pieces, const square_t sq,
+bitboard_t hq_rank_moves(const bitboard_t occ, const square_t sq);
+bitboard_t hq_moves(const bitboard_t pieces, const square_t sq,
                            const bitboard_t mask);
-bitboard_t hyperbola_file_moves(const bitboard_t occ, const square_t sq);
-bitboard_t hyperbola_diag_moves(const bitboard_t occ, const square_t sq);
-bitboard_t hyperbola_anti_moves(const bitboard_t occ, const square_t sq);
+bitboard_t hq_file_moves(const bitboard_t occ, const square_t sq);
+bitboard_t hq_diag_moves(const bitboard_t occ, const square_t sq);
+bitboard_t hq_anti_moves(const bitboard_t occ, const square_t sq);
 
-bitboard_t hyperbola_bishop_moves(const bitboard_t occ, const square_t sq);
-bitboard_t hyperbola_rook_moves(const bitboard_t occ, const square_t sq);
-bitboard_t hyperbola_queen_moves(const bitboard_t occ, const square_t sq);
+bitboard_t hq_bishop_moves(const bitboard_t occ, const square_t sq);
+bitboard_t hq_rook_moves(const bitboard_t occ, const square_t sq);
+bitboard_t hq_queen_moves(const bitboard_t occ, const square_t sq);
 
-#endif  /* _HYPERBOLA_QUINTESSENCE_H */
+#endif  /* _HQ_H */
diff --git a/src/move-gen.c b/src/move-gen.c
index e14f646..8336de7 100644
--- a/src/move-gen.c
+++ b/src/move-gen.c
@@ -99,7 +99,7 @@ bool pseudo_is_legal(const pos_t *pos, const move_t move)
             bitboard_t exclude = BIT(ep + sq_up(them)) | BIT(from);
             bitboard_t rooks = (pos->bb[them][ROOK] | pos->bb[them][QUEEN]) & rank5;
 
-            return !(hyperbola_rank_moves(occ ^ exclude, kingsq) & rooks);
+            return !(hq_rank_moves(occ ^ exclude, kingsq) & rooks);
         }
     }
     return true;
@@ -394,13 +394,13 @@ movelist_t *pos_gen_pseudo(pos_t *pos, movelist_t *movelist)
     from_bb = pos->bb[us][BISHOP] | pos->bb[us][QUEEN];
     while (from_bb) {
         from = bb_next(&from_bb);
-        to_bb = hyperbola_bishop_moves(occ, from) & dest_squares;
+        to_bb = hq_bishop_moves(occ, from) & dest_squares;
         moves = moves_gen(moves, from, to_bb);
     }
     from_bb = pos->bb[us][ROOK] | pos->bb[us][QUEEN];
     while (from_bb) {
         from = bb_next(&from_bb);
-        to_bb = hyperbola_rook_moves(occ, from) & dest_squares;
+        to_bb = hq_rook_moves(occ, from) & dest_squares;
         moves = moves_gen(moves, from, to_bb);
     }
 
diff --git a/src/move.c b/src/move.c
index 23720d3..52b44c0 100644
--- a/src/move.c
+++ b/src/move.c
@@ -152,15 +152,13 @@ move_t move_from_str(const char *str)
 
 /**
  * move_find_in_movelist() - find a partial move in movelist.
- * @target:  partial move
- * @list:    &movelist_t to search
+ * @move:      move (may be partial)
+ * @movelist:  &movelist_t to search
  *
- * Look for @target into @list. @target must at least contain from and
- * to square, as well as promotion information - see move_from_str().
- * If these three pieces of information match, the corresponding move in
- * @list is returned.
+ * Look for @target into @list, by comparing its from, to, and promotion
+ * information.
  *
- * @return: move, or MOVE_NONE if error.
+ * @return: move in @movelist if match found, MOVE_NONE otherwise.
  */
 move_t move_find_in_movelist(move_t target, movelist_t *list)
 {
diff --git a/src/position.c b/src/position.c
index a64e578..3a3e868 100644
--- a/src/position.c
+++ b/src/position.c
@@ -218,7 +218,7 @@ void pos_set_checkers_pinners_blockers(pos_t *pos)
     attackers = pos->bb[them][BISHOP] | pos->bb[them][QUEEN];
 
     /* targets is all "target" pieces if K was a bishop */
-    targets = hyperbola_bishop_moves(occ, king) & occ;
+    targets = hq_bishop_moves(occ, king) & occ;
 
     /* checkers = only opponent B/Q */
     tmpcheckers = targets & attackers;
@@ -229,7 +229,7 @@ void pos_set_checkers_pinners_blockers(pos_t *pos)
 
     /* we find second targets, by removing first ones (excl. checkers) */
     if (maybeblockers) {
-        targets = hyperbola_bishop_moves(occ ^ maybeblockers, king) ^ tmpcheckers;
+        targets = hq_bishop_moves(occ ^ maybeblockers, king) ^ tmpcheckers;
 
         /* pinners = only B/Q */
         tmppinners = targets & attackers;
@@ -244,14 +244,14 @@ void pos_set_checkers_pinners_blockers(pos_t *pos)
 
     /* same for rook type */
     attackers = pos->bb[them][ROOK] | pos->bb[them][QUEEN];
-    targets = hyperbola_rook_moves(occ, king) & occ;
+    targets = hq_rook_moves(occ, king) & occ;
 
     tmpcheckers = targets & attackers;
     checkers |= tmpcheckers;
 
     maybeblockers = targets & ~tmpcheckers;
     if (maybeblockers) {
-        targets = hyperbola_rook_moves(occ ^ maybeblockers, king) ^ tmpcheckers;
+        targets = hq_rook_moves(occ ^ maybeblockers, king) ^ tmpcheckers;
         tmppinners = targets & attackers;
         while (tmppinners) {
             pinner = bb_next(&tmppinners);