
1) Add force to 2) Alter 3) Beef up 4) Bolster 5) Boost 6) Boost up 7) Brace 8) Build up 9) Buttress 10) Change 11) Emphasize 12) Encourage 13) Firm up 14) Fortify 15) Gain strength 16) Give a healthy elasticity to 17) Give a lift 18) Give strength to 19) Harden 20) Highlight 21) Lift 22) Make strong or stronger
Found on
https://www.crosswordclues.com/clue/strengthen

1) Anneal 2) Beef up 3) Boost 4) Buttress 5) Consolidate 6) Fortify 7) Intend 8) Intensify 9) Intensiphi 10) Nourish 11) Reenforce 12) Refresh 13) Reinforce 14) Restrengthen 15) Ruggedise 16) Ruggedize 17) Stabilise 18) Steel 19) Toughen
Found on
https://www.crosswordclues.com/clue/strengthen

• (v. t.) To animate; to encourage; to fix in resolution. • (v. t.) To make strong or stronger; to add strength to; as, to strengthen a limb, a bridge, an army; to strengthen an obligation; to strengthen authority. • (v. i.) To grow strong or stronger.
Found on
http://thinkexist.com/dictionary/meaning/strengthen/

Strength'en transitive verb [ imperfect & past participle Strengthened ; present participle & verbal noun Strengthening .] 1. To make strong or stronger; to add strength to; as, to strengthen a limb, a bridge, an army; to
Found on
http://www.encyclo.co.uk/webster/S/209

[
v] - make strong or stronger 2. [v] - gain strength
Found on
http://www.webdictionary.co.uk/definition.php?query=strengthen
verb make strong or stronger; `This exercise will strengthen your upper body`; `strengthen the relations between the two countries`
Found on
https://www.encyclo.co.uk/local/20974

to make stronger; give strength to. · to change (a speech sound) to an articulation requiring more effort, as from fricative to stop or nongeminate to geminate.
Found on
https://www.infoplease.com/dictionary/strengthen
No exact match found.