We also have a great number of ways 'block' is used. I have listed each below, and categorized cards as best I can:
The Basics
"If (one)/When/While blocking (blocks)..."
This group is fairly easy, and doesn't have much of a question right now. Blocking is being used as the condition for allowing the ability to continue.
Alexander
Asherah Pole
Assyrian Siege Army
Assyria's Tribute
Babylonian Soldiers
Damsel with Spirit of Divination
Elymas the Sorcerer
Emperor Caius Caligula
Gates of Jerusalem - trigger
Gifts for Esau
Guards
Herod Agrippa II
Herod's Dungeon - trigger
Jerusalem
Judaizers
King Amon
King Menahem
King Rehoboam
Lystra
Oppressed and Robbed
Orpah
Pontius Pilate
Prison Guards
Queen Tahpenes
Roman Prison
Sabbath Breaker
Sisera
Stone Throwers
The Amalekits' Slave
The Assryian Spoilers
The Imperial Guard
The Jeering Youths
The Thief
Women as Snares
The Old Wording and Other Abilities
Ignore
Old wording for ignore, not relevant.
Cross Beams of the Cross
Eve
King David
Lot
Nabal
Nichodemus
Scarlet Line
Three Nails
Widow
Witnesses to Creation
Choose the Blocker
Old/different wording for CTB. Not relevant.
Asahel
Ehud
Jael
King Amaziah
Obedience of Noah
Provisions
Withdraw
Struck with Blindness
Withdraw and Present
Death of Firstborn
Lion Dwelling With the Calf
Other
Defiant
Interceding for Battle
Masquerading
Wings of Calamity
The Status Quo
These don't change or need clarification at all, and haven't been an issue.
"Blocker may..."
Boasting of Wisdom
"...a/all blocking Evil Character(s)..."
Visions
Zelophehad's Sin
"...blocker has/may..."
The Darkness
Weakness
Woman of Wisdom
"...successfully blocks..."/"If block is successful..."
Chief Captain Lysias
Fallen Warrior
King Ben-Hadad I
King Shishak
King Tiglath-Pileser III
Lot's Daughters
"...after block..."
King Zimri
"...from being forced to block..."
Kingdoms of the World
The Problem Children
These are the ones where the wording gets questioned most, but I think the definition handles them all. Basically, when an EC is placed in battle where no others are, then you "are blocked" for cards like The Throne of David. The hero(es) are considered to be "blocked by" ALL of the EC in battle, so Angel's Sword works no matter the order they enter.
"If blocked.../If opponent's X blocks.../If X is blocking.../When X is blocked..."
Angel's Sword
House in Bethany
I Am Love
Obadiah
Priests of Christ
Seraiah the High Priest
Spear and Shield
The Throne of David
"When/after blocker is presented..."
Same as "block" where it is only when an EC is put in battle where none is already to oppose hero(es).
Helmet of Brass
Eleazar, son of Aaron
Issue?
"Each time X blocks..."
This one may seem inconsistent, and to have a clear and concise definition that has TToD worded the way it is, this one may get ruled a different way. However, with the way that it is worded with "each time" we should be able to maintain the status quo.
Thorn in the Flesh
Given these different wordings and interactions, I propose the collaborative definition in the first post. Feel free to poke holes or tell me I messed up. I am very tired now.