Webster's Revised Unabridged Dictionary · 1913

Fortify

Fortify , transitive verb

[French fortifier, Latin fortificare; fortis strong + -ficare (in comp.) to make. See Fort, and -fy.]

1.
To add strength to; to strengthen; to confirm; to furnish with power to resist attack.
Timidity was fortified by pride. — Gibbon
Pride came to the aid of fancy, and both combined to fortify his resolution. — Sir W. Scott
2.
To strengthen and secure by forts or batteries, or by surrounding with a wall or ditch or other military works; to render defensible against an attack by hostile forces.

Fortify , intransitive verb

To raise defensive works. — Milton