- totally ordered loop
- totally ordered ring
- totally ordered semigroup
- totally ordered set
- totally ordered subset
- totally orthogonal manifold
- totally orthogonal plane
- totally orthogonal space
- totally positive
- totally positive element
- totally positive field
- totally positive matrix
- totally positive number
- totally projective group
- totally ramified extension
- totally real CR structure
- totally real field
- totally real submanifold
- totally recursive subclass
- totally reflexive relation
- totally regular method
- totally regular ring
- totally regular transformation
- totally sigma-finite measure
- totally singular subspace