Half-pin
Two pieces of the same colour are placed so that when one moves the other is pinned. The theme is indicated if self-pinned and self-pinning pieces exchange their role in two phases.
See also: Anticipatory half-pin.
Blaustein, Yeshayahu
Israel Ring Tourney, 1967
2nd HM
h#2 2.1... (6+6)
1.Qa6
Qf6
2.Bb5
c4#
1.Qa3
Qg5
2.Rb3
c3#
Half-pin (black).
Piliczewski, Bogusz
The Problemist, 2013
2nd HM
h#3 4.1... (6+9)
1.Sb1
Sxe4
2.Sc3
Sc2
3.Sexd5
Sd2#
1.Sxd5
Sd1
2.Sc3
Sc2
3.Sb3
Sde3#
1.Sb3
Sxf3
2.Sd4
Sa2
3.Sxd5
Sd2#
1.Sc2
Sxf5
2.Sd4
Sa2
3.S2b3
Se3#
Half-pin (white).